Gyhlesten Back Jessica, Engberg Göran
Materials Science Division, Dalarna University, 791 88 Falun, Sweden.
Research and Development, SSAB Europe, 781 84 Borlänge, Sweden.
Materials (Basel). 2017 Apr 26;10(5):453. doi: 10.3390/ma10050453.
Crystallographic reconstruction of parent austenite grain boundaries from the martensitic microstructure in a wear resistant steel was carried out using electron backscattered diffraction (EBSD). The present study mainly aims to investigate the parent austenite grains from the martensitic structure in an as-rolled (reference) steel sample and samples obtained by quenching at different cooling rates with corresponding dilatometry. Subsequently, this study is to correlate the nearest cooling rate by the dilatometer which yields a similar orientation relationship and substructure as the reference sample. The Kurdjumov-Sachs orientation relationship was used to reconstruct the parent austenite grain boundaries from the martensite boundaries in both reference and dilatometric samples using EBSD crystallographic data. The parent austenite grain boundaries were successfully evaluated from the EBSD data and the corresponding grain sizes were measured. The parent austenite grain boundaries of the reference sample match the sample quenched at 100 °C/s (CR100). Also the martensite substructures and crystallographic textures are similar in these two samples. The results from hardness measurements show that the reference sample exhibits higher hardness than the CR100 sample due to the presence of carbides in the reference sample.
利用电子背散射衍射（EBSD）对耐磨钢马氏体微观组织中的原始奥氏体晶界进行了晶体学重构。本研究主要旨在研究热轧（参考）钢样品以及通过不同冷却速率淬火并进行相应热膨胀测量得到的样品中的马氏体结构的原始奥氏体晶粒。随后，本研究旨在将热膨胀仪测得的最接近的冷却速率与参考样品产生相似取向关系和亚结构的冷却速率相关联。使用库尔久莫夫-萨克斯取向关系，利用EBSD晶体学数据从参考样品和热膨胀测量样品中的马氏体边界重构原始奥氏体晶界。从EBSD数据成功评估了原始奥氏体晶界，并测量了相应的晶粒尺寸。参考样品的原始奥氏体晶界与在100℃/s（CR100）下淬火的样品相匹配。这两个样品中的马氏体亚结构和晶体织构也相似。硬度测量结果表明，由于参考样品中存在碳化物，参考样品的硬度高于CR100样品。
