摘要
选用一种球化碳钢的轴对称光滑和不同缺口拉伸试样研究了材料在三轴应力场中的宏、微观断裂延性。基于不同应力三轴性水平下空穴扩张与聚合的特性,给出了一个新的材料微观断裂延性表达式。结合空穴扩张的临界尺寸与断口韧窝几何的三维测量结果,证明了在不同的三轴应力水平下,材料微观断裂延性与实测宏观断裂延性之间均有着良好的一致性。从而揭示了材料断裂延性随应力三轴性水平升高而下降的微观机理。
The investigation were performed on the macro-and and micro-fracture-ductility
of materials in triaxial stress field by using axisymmetrical smooth and various
notched tension specimens of a kind of spheroidized carbon steel. Based on the
characteristics of void growth and coalescence at different stress triaxiality levels,
a new expression for micro-fracture-ductility was given. The micro-fracture-
ductility predicted was proven to be in better accordance with the macro-frac-
ture-ductility measured experimentally at different triaxial stress levels, com-
bining with the results in measuring the critical dimensions of growing voids
and dimple-geometry on the fracture surfaces. Thus the micro-mechanisms on
the decreasing of material's fracture-ductility with increased stress triaxiality
levels were revealed.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
1991年第1期25-31,共7页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金
关键词
延性
空穴
扩张
断裂
金属材料
void growth
fracture ductility
stress triaxiality
dimples
