摘要
研究马氏体相变中原子的位移方式具有重要理论意义。本文从理论上综合分析了奥氏体转变为马氏体过程中原子的移动方式。奥氏体转变为马氏体时,在相变驱动力作用下,原子主要是按照K-S位向关系从奥氏体晶格中直接转移到马氏体晶格上去的。当γ→α马氏体时,以晶体缺陷为起点出现涨落,原子无扩散的,集体协同位移,进行了晶格参数的调整,完成γfcc→αbcc-M的晶格重构。原子移动距离远远小于一个原子间距,比K-S切变位移小一个数量级,耗能小。奥氏体转变为马氏体将产生应变能,为了调整应变能和适应新旧相晶格匹配,而形成相变位错、层错或相变孪晶等晶体缺陷以调整应变能,从而完成马氏体晶格重构。切变位移"理论"是错误的。
It is significant theoretically to study the atomic displacement mode during martensite phase transformation. The atomic displacement mode during the transformation from austenite to martensite was synthetically analyzed in theory. During the transformation,the atoms mainly directly shift from austenitic lattice to martensite lattice according to the K-S orientation relationship worked by the phase transformation driving force. When γ transforms to α,the fluctuations first appear in the crystal defects,then the atoms shift by the way of the collective collaborative displacement without diffusion making the adjustment of lattice parameters,thus completes the lattice reconstruction from γfcc→αbcc-M. The atomic displacement distance in this mode is much smaller than an atomic spacing,which is smaller than that in the shear displacement an order of magnitude,so it consumes energy smaller. Since the strain energy emerges in the transformation from austenite to martensite,the substructure of the dislocation,stacking fault or twin crystal can form to adjust the strain energy. The theory of the shearing displacement is improper.
出处
《热处理技术与装备》
2018年第1期1-8,共8页
Heat Treatment Technology and Equipment
基金
内蒙古自然科学基金:2012MS0805
关键词
马氏体相变
无扩散
应变能
集体协同位移
切变位移
martensite phase transformation
diffusion free
strain energy
collective collaborative dis-placement
shearing displacement
