摘要
利用TEM研究了走向凝固方法制备的NiAl－28Cr－5．5Mo－0．5Hf（原子分数，％下同）共晶合金的微观组织与结构，以了解其复相强韧化机及其晶合金呈典型的胞状结构，并由层片状Cr（Mo）相，NiAl基体，不连续网状分布的Heusler相Ni2AlHf组成．NiAl和Cr（Mo）相存在固定的立方－立方取向关系，并共同沿（111）方向生长，两相间呈半共格界面，并存在三套规则的界面错配位错网．在Cr（Mo）相中，发现两种NiAl析出相，分别与Cr（Mo）相呈共格和半共格关系在NiAl基体中，也发现细小的Cr（Mo）相．Heusler相与NiAl或Cr（Mo）相不存在固定的取向关系，但在某些情况下发现二者也存在严格的立方－立方取向关系．
The microstructure of a directionally solidified NiAl-28Cr-5.5Mo-0.5Hf eutectic alloyhas been investigated by TEM. The eutectic alloy has a typical cellular structtire and is composed of threephases which are NiAl matrix, layered Cr(Mo) phase, discontinuously distributed heusler phase Ni2AlHf.There is a cube-cube crystallographic relation between NiAl and Cr(Mo) phases and their grawth directionis (111). The interface between two phases is semi-coherent, at which three sets of interface dislocationsexist. Two kinds of NiAl precipitate were found in Cr(Mo) phase,whereas the precipitation of Cr(Mo) phasewas also found in NiAl matrix. Occationally, a cube-cube crystallographic relation was found betweenHeusler phase Ni2AlHf and NiAl phase.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1999年第9期897-901,共5页
Acta Metallurgica Sinica
基金
国家自然科学基金!9831020
59895156
59871055
