比例与非比例加载下多轴疲劳断口分析  

MULTIAXIAL FATIGUE FRACTOGRAPHIC ANALYSIS SUBJECTED TO PROPORTIONAL AND NONPROPORTIONAL LOADINGS

作　　者：尚德广[1] 

机构地区：[1]北京工业大学机电学院,北京100022

出　　处：《机械强度》2006年第3期392-396,共5页Journal of Mechanical Strength

基　　金：国家自然科学基金资助项目(10172010);北京市拔尖创新人才计划项目。~~

摘　　要：利用扫描电镜对多轴比例和非比例加载下的薄壁管多轴疲劳试样的断口表面进行扫描观测分析。根据试件不同加载路径下的疲劳断口观测结果,研究多轴疲劳裂纹萌生及扩展机理。结果分析表明,比例加载下疲劳断口形式与单轴情况相似,具有Ⅰ型疲劳条纹特征。非比例加载下断口形式主要表现为Ⅰ型与Ⅱ型混合型断口特征。结合多轴非比例加载下的宏观力学条件,在微观机理方面探讨多轴非比例循环下的附加强化机制。The fatigue fracture surfaces of multiaxial fatigue specimens subjected to proportional ann non-proportional multiaxial loadings were observed and analyzed by using the scan electron microscope. According to the observed results of the fatigue fracture surfaces, the mechanisms of fatigue crack initiation and propagation were studied, and the muhiaxial non-proportional loading conditions on the appending hardening mechanism were discussed. The results indicated that the characteristic of model I fatigue striations was shown under proportional loading, and the fracture behavior of mix model Ⅰ and model Ⅱ fatigue strip was shown under nonproportional loading.

关 键 词：多轴疲劳 断口分析 疲劳裂纹扩展 比例加载 非比例加载 

分 类 号：O345.2[理学—固体力学] TH114[理学—力学]