Crystallographic Analysis of Martensite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel using EBSD

• 来源期刊: 材料科学技术学报：英文版
• 学科: 工学
• 关键词: 马氏体板条 晶体学分析 EBSD 电子背散射衍射 钢 数据包 形态学 晶体形成
• 年，卷（期）: 2011,（10）
• 页码范围: 920-930
• 页数: 11页
• 分类号: TG161|O722.7
• 语种: 英文

摘要

The crystallography of martensite formed in 0.2C-2.0Mn-1,5Si-0.6Cr steel was studied using the electron backscattered diffraction （EBSD） technique. The results showed that the observed orientation relationship （OR） was closer to that of Nishiyama-Wassermann （N-W） than Kurdjumov-Sachs. The martensite consisted of parallel laths forming morphological packets. Typically, there were three different lath orientations in a morphological packet consisting of three specific N-W OR variants sharing the same {111} austenite plane. A packet of martensite laths with a common {111} austenite plane was termed a crystallographic packet. Generally, the crystallographic packet size corresponded to the morphological packet size, but occasionally the morphological packet was found to consist of two or more crystallographic packets. Therefore, the crystallographic packet size appeared to be finer than the morphological packet size. The relative orientation between the variants in crystallographic packets was found to be near 60°〈110〉, which explains the strong peak observed near 60° in the grain boundary misorientation distribution. Martensite also contained a high fraction of boundaries with a misorientation in the range 2.5-8°. Typically these boundaries were found to be located inside the martensite laths forming sub-laths.