摘要
利用原位观察技术研究了微岛状试样在25~1100℃连续升降温过程中的显微组织演变。结果表明,与块体材料相同,微岛状试样在给定的升降温工艺下经历了室温组织的分解、奥氏体形核、长大和马氏体相变3个转变过程。原位观察结果揭示晶界、孪晶界和相界能有效提供马氏体相变的形核质点,促进马氏体相变,同时也能作为有效障碍阻挡马氏体板条的生长。与块体材料相比,无束缚态微岛状试样的马氏体相变过程具有明显的先后顺序,其优先性依赖于与块体材料相连接处的相对位置,阐明马氏体相变并非单个晶粒行为,而是大范围晶粒之间的相互协调及互相促进过程。晶粒内形成的马氏体具有板条、板条束和板条群3种层级结构,发生相变时无明显的变体选择倾向。
The microstructurel evolution of micro-island-like sample during continuous temperature rise and fall(25-1100℃)was investigated by in situ observation.The results show that three processes are observed in the micro-island-like sample at the given heating and cooling process in accordance with block-like sample,including the decomposition of microstructure,nucleation and growth of austenite and martensitic transformation.The results indicate that grain boundaries,twin boundaries and phase boundaries can effectively provide nucleation sites of martensitic transformation and promote the martensitic transformation.Also,the boundaries can impede the growth of martensitic lath.In comparison with block-like sample,the martensitic transformation of micro-island-like sample follow an obvious sequence,and its priority depends on the position of connection with block-like sample.This demonstrates that the martensitic transformation is an inter-coordination and mutual promotion process among grains instead of transformation behavior in a single grain.In addition,the martensite has three substructures,including lath,block and packet.And no evident variant selection is found.
作者
王金亮
巫嘉虎
王雨欣
习小慧
WANG Jinliang;WU Jiahu;WANG Yuxin;XI Xiaohui(School of Mechanical Engineering,Guangdong Ocean University,Zhanjiang 524088,China)
出处
《热加工工艺》
北大核心
2023年第10期107-111,共5页
Hot Working Technology
基金
国家自然科学基金资助项目(52101133)
湛江市资助项目(2022B01043)。
关键词
低碳低合金钢
微岛状试样
马氏体相变
原位分析
low carbon low alloy steel
micro-island-like sample
martensitic transformation
in situ analysis
