マルチフェーズフィールド(MPF)法によるミクロ凝固組織形態と凝固温度区間の解析
福元 成雄, 吉岡 優馬
pp. 1-8
DOI:
10.2207/qjjws.37.1抄録
The effects of C content on microsegregation and brittleness temperature range (BTR) were investigated in Fe-Cr-Ni-C alloys, which form the basis for austenitic stainless steel, with primary γ solidification both in the A mode (fully γ) and the AF mode (intercellular eutectic δ) by using the multi-phase field (MPF) method. With increasing C content, cell/dendrite transition occurred in the solidification microstructure and the BTR increased. The estimated influence of C content on BTR agreed well with previous reports. It was thought that the effect of microstructural morphology on BTR was not large. It was also predicted that the microsegregation of Cr also increased with increasing C content, which had strong thermodynamic interactions with Cr. It was also shown that BTR was largely reduced upon changing the solidification mode from A to AF. It was evaluated that the distribution of Cr, Ni, and C varied by adding δ-ferrite in the final solidification region.