【摘要】 通过SiCp/A356颗粒增强复合材料切口试样在20℃~300℃循环下的热疲劳试验,获得热疲劳裂纹形成寿命与试样切口半径及厚度等几何尺寸的关系。采用热弹塑性有限元法模拟热疲劳试验中试样切口根部的应力-应变响应,进而揭示出残余应力形成机制。结合热疲劳试验的裂纹形成寿命与有限元模拟的应力-应变响应,建立起考虑平均应力影响的热疲劳应变寿命曲线,为高速列车SiCp/A356颗粒增强复合材料制动盘的热疲劳性能评价提供依据。更多还原

【Abstract】 Thermal fatigue tests are carried out to the notch specimens made of particle-reinforced composites entitled SiCp/A356 between 20℃ and 300℃.The test results show that the thermal fatigue crack initiation lives of different specimens are relative to the notch radius and specimen thickness.The thermal elastic-plastic finite element method is used to simulate the stress and strain response at the notch root of the thermal fatigue test specimen,and thus the formation mechanism of residual stress is revealed.Then according to the thermal fatigue crack initiation life tests and finite element simulation of the stress-strain,the thermal fatigue strain life curves of SiCp/A356 material are given considering the residual stress.This can give the basis for the thermal fatigue property study of the particle reinforced composite SiCp/A356 used in high-speed train brake disc.更多还原