Identification and Formation Mechanism of a Deformation Process Determining Microstructure of Type IV Creep Damage of the Advanced High Cr Containing Ferritic Heat Resistant Steel
Identification and Formation Mechanism of a Deformation Process Determining Microstructure of Type IV Creep Damage of the Advanced High Cr Containing Ferritic Heat Resistant Steel
复制标题
先进高铬铁素体耐热钢IV型蠕变损伤组织变形过程识别及形成机制
DOI：
10.2355/tetsutohagane1955.92.10_609
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发表时间：
2006
影响因子：
0.3
通讯作者：
M. Ohgami
中科院分区：
文献类型：
--
作者：
Y. Hasegawa;T. Muraki;M. Ohgami
根据700 ℃的温度加速蠕变试验，对晶粒热影响区和双相热影响区进行了分析。室温拉伸强度在Ac1转变点附近最低，由快速加热测得。因此，IV型损伤并不符合传统的热影响区软化现象，经常观察到的低碳钢。薄箔透射电镜观察表明，细晶区位错亚结构由球状亚晶组织和粗化碳化物组成。这可能是热影响区热循环和焊后热处理的结果：具有板条马氏体组织的母材在Ac3点以上加热一次，然后立即冷却并转变。这种“弱”板条马氏体组织，明显的模糊板条马氏体，很容易恢复到球状马氏体，
grain HAZ and dual phase HAZ, according to the temperature acceleration creep test at 700•Ž. The tensile strength at room temperature was the lowest at around Ac1 transformation point, determined by rapid heating diratometry. Therefore, the Type IV damage did not coincident the conventional HAZ softening phenomenon often observed in low carbon steels. Dislocation substructure of the fine grain zone is composed of the globular sub-grain microstructure and the coarsened carbide through the Transmission Electron Microscope observation of thin foils. They were possibly explained to be formed through the thermal cycle of HAZ and Post Weld Heat Treatment as follows: a base metal with lath martensite microstructure is warmed above Ac3 point once, and immediately cooled and transformed. Such "weak" lath martensite structure, apparent ambiguous lath martensite, was easily recovered to the globular