QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY
New Arrival Alert : OFF

You can use this feature after you logged into the site.
Please click the button below.

Log in / Sign up
PRINT ISSN: 0288-4771

QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol. 3 (1985), No. 4

  • Electron Beam Welding of High Manganese Steel Structure

    pp. 678-683

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.678

    High power electron beam welding was applied to manufacture heavy plate welded structure made of high manganese steel in production.
    The electron beam welding machine was of high vacuum type with maximum output of 110 KW, the types of steel were 14%Mn-2%Cr-2%Ni-0.6%C, 18%Mn-5%Cr-0.5%C and 18%Mn-5%Cr-0.6%C with V and N, and the penetration depth was 40 to 70 mm.
    This report described an effect of P and N content on the solidification crack occurrence, characteristic penetration depth and mechanical properties in electron beam welded joints of these high manganese steels and practical welding of heavy plate products.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Investigation of Welding Phenomena in Resistance Pressure Welding Using Insert Material

    pp. 683-690

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.683

    A resistance pressure welding method using insert material was investigated. In this method, a layer of insert material (BNi-2, SUS304, BAg-1) was placed between two base metals to raise electrical contact resistance, and electric current was passed through the layer causing concentrated heating at the interface. The molten layer of low melting point was pressed out of the joint interface. Various types of insert materials were tried for joining SUS304 stainless steel. Metallography of the joint sections was investigated. It was found that BNi-2 with high hardness with high hardness and reaction for base metal gave better joint characteristics of high tensile strength, small deformation and homogeneity of the joint layer.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Fundamental Study for Resistance Brazing

    pp. 690-696

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.690

    The heat source of resistance brazing is electric resistance heating. Therefore the same principles as those for other resistance welding are considered to be applied. However the mechanism of heating and the correlation between the brazing conditions and the strength of brazed joint are less known. It is interesting to investigate the problems of brazing process from the view point of resistance welding process. The authors made small braze area on lap joint specimens similar to resistance spot welding, then tested and analyzed the effects and correlation between elements of resistance brazing condition comparing with those for resistance spot welding. Thus the following fundamental data has been obtained.
    The behavior of resistance brazing is very similar to that of resistance spot welding. The correlation between the elements of condition has similar characteristics. The strength of braze increases in proportion to brazing current and brazing time. When the increase rate is saturated, fusion zone similar to nugget of spot weeding is formed. When this phenomenon appears, the strength per a unit area decreases rapidly. And the base metal is heat affected.
    Resistance brazing is operated relatively easily, and strength obtained is stable and reliable with optimum schedules.
    The voltage drop characteristics at the brazed area observed with an oscillograph is vrey similar to that of resistance spot welding. By analyzing it, it becomes possible to choose appropriate conditions of brazing and control the operation.
    The choice of electrode is important. Carbon graphite is of low cost, but has the following shortcoming. The magnitude of current varies remarkably depending on its size, especially decreases exponentially with increase in the thickness.
    The surface of material to be brazed and electrode sticks to each other owing to temperature increase before the current duration to obtain the maximum tensile shear load is reached, which. causes a problem in practical operation.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Friction Welding of Sintered Steel and Carbon Steel

    pp. 696-702

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.696

    The friction weldability of sintered high carbon-high chromium steel (PM) and S25C steel was investigated. The welded joint of the as-received PM and S25C steel, the quench-tempered joint after welding and the welded joint of the quench-tempered PM and the as-received S25C steel were made. They were labelled A, B and C joints. A continuous drive type friction welding machine was used. Welding was carried out in the range of the following conditions.
    Rotational speed: 2440 rpm,
    Friction pressure: 6.0, 8.0 Kgf/mm2,
    Upsetting pressure: 10.0, 14.0 Kgf/mm2,
    Friction time: 3.0, 5.0 s,
    Upsetting time: 10.0 s.
    Results of this study are summarized as follows:
    (1) The A joint are broken in the PM base metal or at the weld in tensile test. As the tensile strength of the as-received PM base metal itself is low, the joint is unsuited for practical use.
    (2) The C joints are broken at the weld interface or in the heat-affected zone of PM base metal in tensile test. The joint imperfection at the weld interface and the imperfection of joint between powder particles are the causes of fracture in each case.
    (3) The B joints are broken in the base metal in tensile test and have sufficient strength.
    (4) The B joint is superior to the quench-tempered PM base metal in bending ductility, impact value and fatigue limit.
    x

    Readers Who Read This Article Also Read

    1. A Study on Formation of Alloyed Layer of Low Melting Temperature on Bonding Surface of IN738LC with Sputtering QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Advanced Technique in Thermal Coating of Ni-Cr Base Self Fluxing Alloy with Temperature Control Method QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Joining of Plain Carbon Steel to Alumina with Copper Filler Metal

    pp. 702-707

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.702

    Joining of plain carbon steel (SS41) to alumina or mullite using copper filler metal was made in a slightly oxidizing atmosphere. Joining strength was determined by fracture shear loading. The liquid copper wetted both alumina and steel during joining, and a strong joining was formed after cooling down. The strong bond is attributable to the formation of hercynite (FeAl2O4) at the interface between copper and α-alumina. The use of this joining provides various type of joints such as alumina/steel tee joint and alumina butt joint strapped with steel.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Relationship of Formatin of Cu-Sn-Ag Alloyed Layer at the Interface of Pb Base Solder and Copper and Joint Properties in Press Soldering

    pp. 707-711

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.707

    In order to increase the strengths of soldered joints, a new press-soldering method was investigated. In this method, materials of low melting points and low strengths (mainly Pb) were discharged from the joint interface and an alloyed layer of high strength was left.
    The lap joint which was press-soldered at 550°C with 3 kgf/mm2 pressure using Pb-1.5%Ag-1%Sn solder fractured at the Cu base plate.
    An alloyed layer which contained mainly Cu, Sn and Ag was formed at the joint interface and Pb was not detected.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Sprayed Aluminium Coating for Corrosion Protection under Thermal Gradient Condition

    pp. 712-717

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.712

    When the organic coatings are exposed to hot water under thermal gradient condition, blisters will form on the organic coating resulting in corrosion of steel substrate in some cases over a short periods of time. Corrosion protective properties of four organic coating and sprayed aluminium coating are studied by the thermal gradient test.
    Main results of the experiment are summarized as follow;
    (1) The sprayed aluminium coating has the best corrosion protective properties of all the other coatings.
    (2) If the sprayed aluminium coating is coated by the thin organic paint, it will give better corrosion protective nrouerties.
    (3) Good adhesion strength of aluminium sprayed coating is obtained by grit-blast or sand-blast cleaning before aluminium spraying.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Advanced Technique in Thermal Coating of Ni-Cr Base Self Fluxing Alloy with Temperature Control Method

    pp. 717-722

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.717

    The automatic control system for spray fused coatings was developed. In this ysstem, Vx(=Vmax·A) which is the traverse speed of a heat source, varies with the temperature of a just treated area, where Vmax is the maximum speed of a heat source, and A is variable (named the temperature coefficient) calculated with a next equation.
    A={(t-TL)/(TH-TL)}n
    where t is the temperature of a just treated area, measured with a pyrometer, TL and TH are lower and higher limit temperatures of treatment set in advance, respectively, and n is a natural number.
    The system was designed for carrying out above control, and the performance of this system was confirmed.
    This automatic control system was applied actually to spray fused coatings of a self-fluxing Ni-base alloy.
    This system made it possible to spray and fuse the alloy satisfactorily, and the most suitable condition of treatment was calrified.
    x

    Readers Who Read This Article Also Read

    1. A Study on Formation of Alloyed Layer of Low Melting Temperature on Bonding Surface of IN738LC with Sputtering QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Friction Welding of Sintered Steel and Carbon Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Mechanical Properties of Disbonding Resistant Overlay Weld

    pp. 722-729

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.722

    It was found out that the first layer overlay weld metal with the austenite/martensite duplex microstructure provided the overlay welds with better hydrogen-induced disbonding resistance than that with the conventional austenitic microstructure containing several percents ferrite as previously reported.
    The purpose of the present study is to determine the mechanical properties of the overlay welds with the duplex weld metal. The main results obtained in this study are as follows:
    1) The ductility of the overlay weld was not decreased by the regular post-wled heat treatment (PWHT), and almost equal to that of the conventional overlay weld.
    2) The absorbed energy values both in the weld metal and at the bond were almost equal to those of the conventional overlay weld before and after PWHT.
    3) The fracture position and fracture mode of the Charpy impact test specimens altered by PWHT.
    4) As the martensite content of the 1st layer weld metal was increased, the values of the residual stress in through-thickness direction of the bond between the duplex weld metal and the base metal were decleased.
    5) This low residual stress was one of the main reasons to provide the overlay weld with good dis-bonding resistance.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Sampled-Data Control of Arc Length and Torch Height Using ITV Image Processing Device

    pp. 729-736

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.729

    The problem for measuring and controlling the arc length and the torch height is important as a basis of research in automatic arc welding systems. Improvement of welding quality requires to keep constant optimum values of the length and current of the arc. In this paper, we discuss the stability and adaptability of the arc length in the MIG pulse arc welding system with a constant feeding speed of the electrode wire. Consequently, it is necessary to control the height of welding torch so as to keep the electrode extension constant for controlling both the current and length of the arc. We construct a basic visual robot which measures and controls the arc length and the torch height, using the personal computer, image processing device, and ITV camera as a sensor. Furthermore, we describe how to determine the characteristic of the digital controller, which controls the welding current and the digital servo motor for controlling the arc length and the torch height. We also introduce a basis of the electric techniques which incorporate the personal computer, image processing device, digital-analog converter, programmable current source, and digital servo motor.
    x

    Readers Who Read This Article Also Read

    1. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Nitrogen Absorption into Pure Iron Weld Metal under Welding Atmosphere of High Pressure QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effects of Ti and Al on Notch Toughness of Synthetic Heat Affected Zone in Steels with Low Nitrogen QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Nitrogen Absorption into Pure Iron Weld Metal under Welding Atmosphere of High Pressure

    pp. 737-744

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.737

    Pure iron was welded in N2 and N2-Ar atmospheres at 1-30 atm pressures. Effects of welding conditions and the nitrogen partial pressure on the nitrogen content of pure iron weld metal were systematically studied. The results are summarized as follows:
    (1) In the nitrogen welding atmosphere, the nitrogen content of weld metal decreased with increasing the welding current, with decreasing the arc voltage and with decreasing the travel speed.
    (2) In the nitrogen welding atmosphere, the nitrogen content of weld metal increased with the nitrogen pressure, but the degree of the increase became slight with increasing the nitrogen pressure. The nitrogen absorption of weld metal does not obey the Sieverts'law.
    (3) In N2-Ar welding atmosphere, the nitrogen content of weld metal was lower in high atmospheric pressure than in low atmospheric pressure at the same nitrogen partial pressure.
    (4) Using thermodynamic data obtained by equilibrium study, the nitrogen absorption into the weld metal in the nitrogen atmosphere of high pressure was discussed. The reaction time in welding process is so short that the nitrogen content of weld metal can not reach the equilibrium value in higher atmospheric pressure.
    (5) All iron weld metals had porosity.
    x

    Readers Who Read This Article Also Read

    1. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Sampled-Data Control of Arc Length and Torch Height Using ITV Image Processing Device QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effects of Ti and Al on Notch Toughness of Synthetic Heat Affected Zone in Steels with Low Nitrogen QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Nitrogen Absorption into Stainless Steel Weld Metal under Welding Atmosphere of High Pressure

    pp. 744-751

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.744

    20Cr-10Ni stainless steel was welded in N2 and N2-Ar atmospheres at 1-30 atm pressures. Effects of welding conditions and the nitrogen partial pressure on the nitrogen content of stainless steel weld metal were systematically studied. The results are summarized as follows:
    (1) In the nitrogen welding atmosphere, the nitrogen content of the weld metal decreased with increasing the welding current and increasing the travel speed, and with decreasing the arc voltage.
    (2) In the nitrogen welding atmosphere, the nitrogen content of the weld metal increased with the nitrogen pressure, but the nitrogen absorption of the weld metal does not obey the Sieverts' law.
    (3) In N2-Ar welding atmosphere, the nitrogen content of the weld metal was lower in high atmospheric pressure than in low pressure at the same nitrogen partial pressure.
    (4) Using thermodynamic data obtained by equilibrium study, the nitrogen absorption into the stainless steel weld metal in the nitrogen atmosphere of high pressure was discussed.
    (5) All stainless steel weld metals had no porosity.
    x

    Readers Who Read This Article Also Read

    1. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    2. Oxygen Content and Fracture Toughness on MIG Weld Metal of SUS304 Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
    3. Mechanical Properties of Low Yield Ratio HT80 Steel and Its Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3
  • Reaction Mechanism of Hydrogen in Electroslag Welding

    pp. 751-757

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.751

    The reaction mechanism of hydrogen transfer in electroslag welding is presented.
    The effects of baiscity of flux and water vapour pressure of atmopshere on hydrogen contents of deposited weld metal in copper moulds with electroslag welding using a consumable nozzle have been investigated.
    It has been found that Sievert's law does not hold in the relation between the hydrogen content of weld metal and water vapour pressure but a linear relation does.
    This relation may hold under the assumption that the water dissolves in slag as hydroxyl combined with silicate networks and free hydroxyl ions and that only hydroxyl ions react with metal.
    The partition coefficient and the reaction rate constant of hydrogen is reversely proportional to the basicity of flux. The former is almost same as the value so far reported in electroslag ramelting and the latter is three to nine times as high as that.
    x

    Readers Who Read This Article Also Read

    1. Nitrogen Absorption into Pure Iron Weld Metal under Welding Atmosphere of High Pressure QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Sampled-Data Control of Arc Length and Torch Height Using ITV Image Processing Device QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effects of Ti and Al on Notch Toughness of Synthetic Heat Affected Zone in Steels with Low Nitrogen QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Effects of Ti and Al on Notch Toughness of Synthetic Heat Affected Zone in Steels with Low Nitrogen

    pp. 758-766

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.758

    Effects of Ti and Al in steels on the notch toughness of the synthetic weld heat affected zone have been investigated using 41 kgf/mm2 grade steels containing various quantities of N. The results obtained are as follows: (1) Synthetic HAZ toughness of the steel containing 13 ppm of N is the most superior to the other all steels. Charpy transition temperature (vTrs) is droped about 15°C per the decreasing of 10 ppm of N. When N in steels is less than 20 ppm, additions of Ti and/or Al deteriorate the notch toughness. (2) Notch toughness is improved by Ti addition, especially, when Ti is added about 3.4 times of N content, the notch toughness becomes the best, because of the decreasing of free N content and the refining of microstructures on each N content of 20 to 60 ppm. (3) Even if the ratio of Ti and N contents, Ti/N, is 3.4, the notch toughness is improved with the decrease in N content of steels. However, when 0.06 wt% of Al is added in steels containing more than 0.015 wt% Ti and more than 50 ppm N the notch toughness is further improved. (4) Optimum Ti content neccesary to improve the notch toughness is 0 wt% in steels containing 10 ppm N, and about 3.4 times of N content in more than 20 ppm N. (5) vTrs of synthetic HAZ of steels containing optimum content of Ti is very low comparing to steel without Ti and this tendency becomes remarkably as N content increases. While the additions of Al are effective in steels with nitrogen above 35 ppm.
    x

    Readers Who Read This Article Also Read

    1. Nitrogen Absorption into Pure Iron Weld Metal under Welding Atmosphere of High Pressure QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Sampled-Data Control of Arc Length and Torch Height Using ITV Image Processing Device QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Distribution of Microstructure in HAZ of Multi-Pass Welded High Strength Steel

    pp. 766-773

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.766

    The characteristic of toughness in weld heat affected zone (HAZ) of multi-pass welded high strength steel was investigated in this study. In multi-pass HAZ, some kinds of microstructure are distributed and toughness can be affected by this microstructure distribution. Therefore, in this report, the distribution of microstructure in HAZ of multi-pass welded 60 kgf/mm2 class high strength steel was investigated.
    The main results obtained were as follows.
    (1) It was confirmed that HAZ was heated above the reverse transformation temperature once, twice or three times by weld thermal cycles. But it was found that the microstructure in HAZ could be almost simulated by single or double thermal cycles.
    (2) Peak temperature of weld thermal cycle could be divided into three regions according to its effect on microstructure. That is, (I) α-γ dual phase region, (II) low hardenability region and (III) hardenability recovered region.
    (3) Microstructure was relatively uniform in the outer and the intermediate part of HAZ. But, in the inner part (that is, near the fusion line), three kinds of microstructures were ditsributed.
    x

    Readers Who Read This Article Also Read

    1. Effect of Postheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Effect of Preheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effects of Micro-Alloy Elements on 2 1/4%Cr-1%Mo Weld Metal Toughness Produced by Narrow-Gap SAW Process QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Distribution of Toughness in HAZ of Multi-Pass Welded High Strength Steel

    pp. 773-781

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.773

    The distribution of toughness in HAZ of multi-pass welded high strength steel was investigated on the basis of the distribution of microstructure which had been discussed in the previous report.
    The main results obtained were as follows.
    (1) The toughness differed with each microstructure which had been classified in the previous report.
    (2) The toughness of each microstructure was improved by the tempering thermal cycles of the following passes. But the degree and the peak temperature range of the improvement were varied according to the indivisual microstructures.
    (3) The toughness was relatively low in the area close to the base metal and high in the intermediate area between the base metal and the weld metal. In the area near the fusion line, low and high toughness regions were distributed alternately.
    x

    Readers Who Read This Article Also Read

    1. Estimation of Cracking Susceptibility of Nodular Graphite Cast Iron with the Implant Test QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Effects of Micro-Alloy Elements on 2 1/4%Cr-1%Mo Weld Metal Toughness Produced by Narrow-Gap SAW Process QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Effects of Micro-Alloy Elements on 2 1/4%Cr-1%Mo Weld Metal Toughness Produced by Narrow-Gap SAW Process

    pp. 781-789

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.781

    In a narrow gap arc welding process with one run per layer technique, the weld metal toughness greatly depends on that of as-dendritic structure, because of the reduced reheated zone compared with the central part of conventional multipass weld metal. With an emphasis on the improvement of asdendritic structure weld metal toughness, the effects of micro-alloying elements such as C, V, Ti, Nb on 2 1/4%Cr-1%Mo SA-weld metal toughness are investigated and the following results are obtained:
    1) The increase of carbon content and V-addition are effective to improve the as-dendritic structure toughness by refinning the bainitic lath sub-structure from the higher hardenability and increasing carbon-nitrides precipitated uniformly within the grains after PWHT.
    2) In 0.12%C-0.07%V bearing weld metal, the difference in toughness between as-dendritic structure and reheated zone is greatly reduced, resulting in homogeneous weld metal.
    3) The addition of Nb and Ti is effective to increase the strength but deteriorates the weld metal toughness due to precipitation hardening.
    4) The optimum chemistry of 2 1/4%Cr-1%Mo weld metal for a narrow gap SAW process is decided to be
    C : 0.12% Cr : 2.25%
    Si : 0.20% Mo : 1.0%
    Mn : 0.70% V : 0.07%
    P : ≤0.010% x : ≤15ppm
    S : ≤0.010%
    x

    Readers Who Read This Article Also Read

    1. Estimation of Cracking Susceptibility of Nodular Graphite Cast Iron with the Implant Test QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Distribution of Toughness in HAZ of Multi-Pass Welded High Strength Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Estimation of Cracking Susceptibility of Nodular Graphite Cast Iron with the Implant Test

    pp. 789-795

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.789

    A study on the cracking susceptibility of nodular graphite cast irons by means of the implant test in different heat inputs is described. The implant test specimens were mainly smoothed 6 mm in diameter ones. Weld heat inputs, with the use of 4 nun diameter DFCNiFe type electrode (55%Ni-Fe), were changed 18, 000, 21, 000 and 24, 000 joules/cm with 10 cm/min travel speed and 50 mm bead length. After welding, when the temperature of the HAZ cooled to about 400°C, the load was applied.
    The implant specimens were fractured at about 100°C, which was below the Ms temperature of the cast irons used. In the heat input variation range of present work when heat input was made higher, the lower critical stress of fracture slightly inrceased; but it went up to only below a half of the strength of the base metal. The implant specimens were fractured at the part of the martensite structure with the highest micro-vickers hardness number, about 900. The fracture surface consisted of mainly intergranular fractures with partly quasi-cleavage fracture mode.
    x

    Readers Who Read This Article Also Read

    1. Effects of Micro-Alloy Elements on 2 1/4%Cr-1%Mo Weld Metal Toughness Produced by Narrow-Gap SAW Process QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Distribution of Toughness in HAZ of Multi-Pass Welded High Strength Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Reaction Mechanism of Hydrogen in Electroslag Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Effect of Preheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds

    pp. 796-801

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.796

    A study on the preheating effect for preventing cracking of heat-affected zone of nodular graphite cast irons (FCD 50) is made by means of the implant cracking test. The apparatus for the implant test, dimensions of the smoothed test specimens and DFCNiFe (55%Ni-Fe) electrodes used for the present study are the same as in the previous report. Weld heat input is 21, 000 Joules/cm.
    When preheating temperature was made higher, the critical rupture stress of the cracking increased: It went up to about 90% of the tensile strength of base metal with preheating at 300°C and 450°C, while it showed only about a half of that strength without preheating. In case of preheating at 300°C and 450°C, the implant specimens were fractured in the unmixed zone which had ledeburite structure. From the studying for the CCT diagram of cast iron used for the present work, the critical cooling time, when the troostite structure appeared at the partially melted zone and true heat-affected zone, from 800°C to 500°C was about twelve seconds. In the present work, this condition was obtained with preheating at 300°C.
    x

    Readers Who Read This Article Also Read

    1. Effect of Postheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Distribution of Microstructure in HAZ of Multi-Pass Welded High Strength Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Comparison of Strength Characteristic of Cast Iron / Mild Steel Welding Joints by Various Welding Process QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.23(2005), No.2
  • Effect of Postheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds

    pp. 801-807

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.801

    A study on the postheating effect for increasing the strength of heat-affected zone of nodular graphite cast irons (FCD 60) is made by means of the implant cracking test. The apparatus for the implant test, dimensions of the smoothed test specimens and DFCNiFe (55%Ni-Fe) electrodes used for the present study are the same as in the previous reports. Weld heat input is 25, 000 Joules/cm. When the temperature near bond line was cooled down to 200°C, postheating using propane burner was started and was lasted to reach the temperature; 300°C, 400°C and 500°C. To study the postheating effect of multilayer sequence, two layer welding was also examined.
    When postheating temperature was set higher, the critical rupture stress of the heat-affected zone increased: It went up to about 80% of the tensile strength of base metal with postheating at 400°C and 500°C while it showed only about a half of that strength with postheating at 300°C and without postheating. In case of postheating at 400°C and 500°C, bainite structure was formed at the true heat-affected zone. This fact was the reason of postheating effect. In case of two layer welding, the critical rupture stress increased to 410 MPa by the postheating effect of second layer bead.
    x

    Readers Who Read This Article Also Read

    1. Distribution of Microstructure in HAZ of Multi-Pass Welded High Strength Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Effect of Preheating on the Critical Rupture Stress of Nodular Graphite Cast Iron Welds QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Distribution of Toughness in HAZ of Multi-Pass Welded High Strength Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Reheat Cracking Phenomena in Ni-Base Superalloy, Waspaloy

    pp. 808-815

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.808

    In this study, the reheat cracking phenomena in Waspaloy was researched to get beneficial information in order to make clear the mechanism of reheat cracking, that often occurred during the post weld heat treatment (PWHT) of Ni-base superalloys.
    Main results obtained in this study are as follows;
    (1) Reheat crackings initiated and propagated at grain boundaries adjacent to the fusion lines in HAZ. The initiation and propagation range shifted to lower stress and temperature sides due to slowing down heating rate to PWHT temperature from 4100°C/min to 30°C/min.
    The critical initiation stress of the reheat cracking also decreased associated with sluggishing heating rate to PWHT temperature.
    (2) Influences of various factors on the local deformability (δc) of coarse-grained zone were investigated, which resulted in following conclusions.
    (a) δc values at 800, 850 and 900°C became constant by using tensile rate less than 2.2 cm./min.
    (b) Minimum δc value was obtained at 850°C.
    (c) The detrimental influence of oxygen-containing environment on δc, at 800, 850 and 900°C during simulating weld thermal cycles was found and oxygen embrittlement was particularly observed in the case of local melting occurring at grain boundaries.
    (d) δc value at 850°C decreased with increase of grain size.
    (e) δc values at 800, 850 and 900°C depended upon hardenability of matrix. Hardening matrix resulted in decreasing δc values at 800, 850 and 900°C.
    (f) The beneficial effect of Ca addition was observed. Adding 50 ppm Ca promoted δc values at 800, 850 and 900°C due to fixing S atoms as Ca-S inclusions.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Behavior of Precipitates in Ni-Base Superalloy, Waspaloy

    pp. 815-822

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.815

    In Ni-base superalloys, mechanical and chemical properties of welded joints depend on the behavior of precipitates such as γ' phase, M23C6 etc. The susceptibilities of solidification cracking, liquation cracking, reheat cracking etc. are also influenced by the behavior of precipitates.
    In the present study, the behavior of precipitates in Waspaloy has been researched to get fundamental information about the behavior of minor phases during welding in Ni-base superalloys.
    Main results obtained in this study are as follows;
    1) Intergranular M23C6 carbides, intragranular r' phases and massive TiC were observed in base metal (1080°C×4 hr, W.Q.).
    2) Precipitated zone heated up to 700-900°C was formed in HAZ. Precipitation of γ' phase and M23C6 carbide was promoted in this region.
    3) During isothermal heat treatment;
    a) Heat treatment at 900-1000°C resulted in most rapid precipitation of M23C6.
    b) γ' phase most rapidly precipitated at about 900°C and γ' phase coarsening was found to obey Lifschitz-Wagner theory.
    c) It was found that increment of hardness by γ' phase precipitation, ΔHv was a linear function of (aging time, t)1/6 within experimental error.
    4) During weld thermal cycle;
    a) M23C6 carbide precipitated at 750-950°C during welding.
    b) Incipient melting of TiC was observed at the temperature more than 1270°C.
    c) γ' phase precipitated at 900-980°C during welding.
    d) γ' phase coarsened in the temperature range from 1000°C to 900°C.
    e) Hardness was a function of cooling time from 1000°C to 700°C.
    5) It was possible to estimate hardness of solution treated material during post weld heat treatment by using the relation between ΔHv and t1/6.
    x

    Readers Who Read This Article Also Read

    1. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effect of Welding Residual Stress on Retardation Behavior due to Over-spike Loading During Fatigue Crack Propagation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Blowholes on Pulsed MAG Welding

    pp. 822-830

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.822

    Blowholes and their formation of Pulsed MAG welding was investigated. Among welding parameters such as arc length, average current, wire extension, welding speed and shielding gases, arc length was the most important factor. The average size of blowholes was as small as 0.62 mm. As results of analysing gas components of the blowholes by means of gas chromatograph, Ar, H2, and CH4 were detected and CO2 and CO and O2 were not in the blowholes. H2 and CH4 were also detected in blank test pieces. From SEM observation, the shape of the blowhole was like a sphere, the bottom of which was flat and the upper side was uneven like a corn having a slag spot at the top. The slag composition in the blowhole was Al, Si, Mn, Ca, La and Ce etc., and differed from the slag on the weld bead. From these results, the mechanism of blowhole formation in Pulsed MAG welding was considered as follows. Disturbance of the weld pool accompanied with spattering forms gas bubbles of the shielding gas in the pool. Small bubbles tend to be dragged into the bottom of the pool by whirling action, and be confirmed there to form blowholes close to the fusion line. CO2 in the blowholes are deoxidized to form the slag at the top of the blowholes.
    x

    Readers Who Read This Article Also Read

    1. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effect of Welding Residual Stress on Retardation Behavior due to Over-spike Loading During Fatigue Crack Propagation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • On Prevention of Cracks in Underwater Wet Welds by Postheating

    pp. 830-836

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.830

    The effect of postheating on occurrence of underbead cracks and root cracks in underwater wet welds by gravity welding process is investigated. Lime titania type coated electrode (D5003) of 4 mm in diameter and SM50A steel base metal of 12 mm in thickness are used.
    Main results obtained are summerized as follows:
    1) Underbead cracks occur in HAS of underwater welds about 5 min after the welding.
    2) Occurrence of underbead cracks and root cracks can be prevented by postheating above 100°C. The critical concentration of hydrogen in weld metal to prevent the occurrence of cracks Cwc is 0.3 ml/100g W.M.
    3) As the condition of postheating, the critical time factor c, by which the critical concentration of hydrogen Cwc is obtained, should be selected.
    4) An argolism to obtain the condition of postheating (τc, tc) from dimensions of weld (l0, l), initial concentration of diffusible hydrogen (C0≈Hw), temperature of postheating (Th) and critical concentration of hydrogen (Cwc) is proposed.
    x

    Readers Who Read This Article Also Read

    1. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effect of Welding Residual Stress on Retardation Behavior due to Over-spike Loading During Fatigue Crack Propagation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Hot Ductility Behaviour of Nickel Alloy Weld Deposits

    pp. 836-843

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.836

    Hot ductility behaviour was investigated for 17 kinds of Nickel alloy weld deposits. The used specimens were prepeared from weld deposits made in the form of pads on Type 304 steel plate using covered electrodes. Then, plastic strains were applied to the specimens in the heating and cooling process of weldsimulation thermal cycle, and critical enforced strain (εHC) capable of initiating cracking were measured. The obtained results are as follows:
    (1) Cracking occurs along grain boundary of dendrite when the plastic strain exceeding εHC values was applied to weld metal specimen.
    (2) When the testing temperature becomes over 1100°C, weld deposits tend to indicate extremely low values.
    (3) Hot ductility, i.e. ego value, depends markedly on the chemical compositions.
    (4) The following equation may predict hot ductility behaviour.
    εHC1200=20[C] -0.5[Mo] -0.5[Nb] -5[T] +2.8
    When the εHC1200 value is over 2, the weld deposit exhibits excellent hot ductility.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Effect of Welding Residual Stress on Retardation Behavior due to Over-spike Loading During Fatigue Crack Propagation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Effect of Welding Residual Stress on Retardation Behavior due to Over-spike Loading During Fatigue Crack Propagation

    pp. 843-851

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.843

    Although many studies concerning about retardation behaviors have been carried out, the effect of residual stress on retardation behavior have not yet been investigated. In the present study, SM50A steel weldments and SUS304 steel weldments were prepared to carried out the fatigue crack growth tests under constant amplitude loading with single over-spike loading. The effect of residual stress can be considered to be equivalent to that of mean stress. The mechanical model to predict delayed retardation behavior was also discussed. The proposed model gives a good agreement with experimental results.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Study of Fatigue Strength of Electron Beam Welded Joint

    pp. 851-856

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.851

    This paper deals with the fatigue strnegth of electron beam welded joint made from the welding structure steel SM41. The cause of the difference in the fatigue strength between electron beam (EBW) and CO2 gas (CO2W) welded joints was investigated by comparing the factors which are the weld reinforcement, the residual stress and the hardness at the neighbourhood of the toe. The fatigue strength of CO2W welded joint was considerably lower than that of the base metal, but the fatigue strength of EBW welded joint was equal to that of the base metal in order to occur fracture in the base metal of EBW welded joint. Therefore, above factors of jonits welded by both welding processes were studied. The values of residual stress in the fatigue specimen machined from the welded joint were nearly zero. The stress concentration factor calculated from the weld reinforcement geometry of EBW was smaller than that of CO2W. The hardness at the toe of EBW welded joint was extremely larger than that of CO2W welded joint. The fatigue test results of notched specimens quenched by high frequency and non-quenched suggested that the difference of the fatigue strength between EBW and CO2W welded joints was caused by both the increasing hardness and the decreasing the stress concentration factor.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Improvement of Fatigue Strength of Al Alloy Welded Joints by Toe-peening

    pp. 856-862

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.856

    In order to improve fatigue strength of Al alloy welded joints, the effects of grinding on weld reinforcements and toe-peening on weld toe lines were investigated. Fatigue tests were carried out on three series of A5083 Al alloy butt welded joints and A7N01 Al alloy cruciform welded joints. Fatigue strength of the treated joints were compared with thatof as welded ones.
    Following results were obtained;
    (1) Toe grinding and reinforcement removal grinding increased the fatigue limits of the butt welded joints by 59% and 120%, respectively.
    (2) The fatigue limit of the peened joints was about 80-120% higher than that of as welded joints.
    (3) The fatigue strength of the joints, thermally stress relieved after peening, was equal to that of as welded joints.
    (4) The effect of the fatigue strength improvement can be attributed to compressive residual stress generated by toe-peening.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Mechanical Properties of Weld Metals Subjected to Thermal Prestraining Cycles and Its Application to Deformation Analysis of Weld Joint

    pp. 862-869

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.862

    Mechanical and metallurgical heterogeneity in wled joints, which is caused by thermal prestraining cycles, have an important effect upon their deformation and strength behaviors. If the mechanical properties of steels and weld metals subjected to thermal prestraining cycles can be estimated conveniently, it is easy to analyze the deformation behaviors of weld joints by use of numerical computation procedures.
    In this study three kinds of weld metals, which are formed at weld joints of a carbon steel (SM41B), an austenitic stainless steel (SUS304) and a martensitic cast steel (SCS5), were used for experiments. Their mechanical properties depended upon the thermal prestraining conditions, for example, peak temperature, retention time at constant temperature, multi-thermal prestraining cycles. The experimental results indicated that elastic limit, yield stress, strength coefficient and strain hardening exponent of materials sub-jected to thermal prestraining cycles could be expressed as a function of Vickers hardness.
    As an application, the material constants for elastic-plastic FEM analysis were determined from the Vickers hardness distribution of weld and butt weld joint were analyzed in terms of plastic zone extension from the view of mechanical heterogeneity.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Ductile Fracture in Type 304 Stainless Steel Weldments

    pp. 869-874

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.869

    The processes of ductile fracture of Type 304 stainless steel weld metal specimens, which are cut from weldments produced by using four types of welding condition, are observed. Although quite few large voids are observed at a relatively low strain level, they have no important role in fracture processes. As soon as micro-voids nucleate at some strain level, which is the stage just before final fracture, they rapidly grow and coalesce. The volume fraction of micro-inclusions which are nuclei of micro-voids, seems to control true fracture strain of weld metal specimens.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • Ultrasonic Flaw Detection of Surface Layer with Focusing Probe

    pp. 875-881

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.875

    The present study proposes a method of ultrasonic nondestructive evaluations of flaws in surface layer which can hardly be detected by the conventional methods, of ultrasonic testing due to lapping of both surface and flaw echoes. The echo patterns for various types of flaws in the surface layer of steel test specimens are measured with a single focusing probe and theoretically analysed by theory of sound, from which the effects of the water distance and the flaw depth on the echo pattern are clarified. Moreover, the applicability of this method with scanning device for inspection of flaws in welds is confirmed by microscopic examination. A summary of the results is as follows.
    When the focus of the ultrasonic beam is beneath the position of flaw, there appear two peaks in the echo pattern which are corresponding to the surface echo and the flaw echo, respectively. As the focus approaches to the flaw position, the peak of flaw echo disappears. This peak of echo consists of multiple echoes and is most conspicuous when the ultrsaonic beam is mostly focused by its multiple reflection and thus its sound pressure is highest. The echo height of flaw depends upon the flaw depth and water distance, and the peak position in the echo pattern is independent from the flaw depth under the constant water ditsance. According to the peak profile of scanning detection for weld interfaces of clad, there are two types of echo patterns, that is, wave-shaped and flat-shaped patterns reflected at interspersed flaws and flat-shaped flaws, respectively.
    x

    Readers Who Read This Article Also Read

    1. On Prevention of Cracks in Underwater Wet Welds by Postheating QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Blowholes on Pulsed MAG Welding QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Hot Ductility Behaviour of Nickel Alloy Weld Deposits QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
  • A Study on Formation of Alloyed Layer of Low Melting Temperature on Bonding Surface of IN738LC with Sputtering

    pp. 881-886

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2207/qjjws.3.881

    Diffusion welding method using alloyed layer with sputtering after Ar ion bombarding on bonding surface of IN738LC has been studied.
    In this report, effect of Ar ion bombardment on oxide film of bonding surface, effect of sputtering condition on formation of alloyed layer and measurement of melting temperature were investigated.
    The results indicated that: oxide film on bonding surface can be removed by Ar ion bombardment, formation rate of alloyed layer is very fast in 3×10-3 Torr Ar and melting temperature of alloyed layer was 1080-1100°C.
    x

    Readers Who Read This Article Also Read

    1. Advanced Technique in Thermal Coating of Ni-Cr Base Self Fluxing Alloy with Temperature Control Method QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    2. Friction Welding of Sintered Steel and Carbon Steel QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.4
    3. Creep Embrittlement of Cr-Mo Steel and Its Evaluation QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY Vol.3(1985), No.3

Article Access Ranking

12 Dec. (Last 30 Days)

  1. Factors to Determine Inclusion Compositions in Molten Steel during the Secondary Refining Process of Case-Hardening Steel ISIJ International Vol.56(2016), No.11
  2. Preface to the Special Issue Entitled “Dynamics in Solid-Liquid Coexistence and Controlling of Segregation during Solidification” Tetsu-to-Hagané Vol.103(2017), No.12
  3. Convergent-Divergent Injection Lance for the Enhancement of Combustion Efficiency of Pulverized Coal at Blast Furnace Tetsu-to-Hagané Vol.103(2017), No.11
  4. Real-time Analysis on Non-uniform Heat Transfer and Solidification in Mould of Continuous Casting Round Billets ISIJ International Vol.44(2004), No.10
  5. Effect of Cold Rolling before Hydrogen Reduction on Reduction Behavior and Morphologies of Oxide Scale on Hot-rolled Low-carbon Steel ISIJ International Vol.57(2017), No.11
  6. Viscosity of Heterogeneous Silicate Melts: Assessment of the Measured Data and Modeling ISIJ International Vol.57(2017), No.11
  7. In Situ Observations of Tensile and Compressive Deformations in Semi Solid Metallic Alloys Using Time-resolved X-ray Imaging Tetsu-to-Hagané Vol.103(2017), No.12
  8. Modeling of Gas-Steel-Slag Three-Phase Flow in Ladle Metallurgy: Part I. Physical Modeling ISIJ International Vol.57(2017), No.11
  9. Effect of MnO on High-Alumina Slag Viscosity and Corrosion Behavior of Refractory in Slags ISIJ International Vol.57(2017), No.11
  10. An Online Rolling Model for Plate Mill Using Parallel Computation ISIJ International Vol.57(2017), No.11

Search Phrase Ranking

12 Dec. (Last 30 Days)

  1. blast furnace
  2. 鉄と鋼
  3. blast furnace permeability
  4. blast furnace productivity
  5. camp-isij
  6. carbon composite iron oxide
  7. blast furnace hearth corrosion
  8. breakout continuous casting
  9. breakout prediction, continuous casting
  10. deoxidation equilibrium