摘要
在MTS万能实验机上对室温大气环境下峰时效态3J21合金的疲劳行为进行研究,并采用扫描电镜(SEM)对宏观断口及微观断口进行分析。结果表明,峰时效态3J21合金的疲劳裂纹主要呈穿晶扩展,沿晶扩展的所占比例较小,疲劳裂纹萌生寿命较低,扩展路径比较平直,扩展速率较大,裂纹扩展抗力较小,疲劳寿命较低;峰时效态3J21合金疲劳断口由疲劳源、疲劳裂纹扩展区和瞬断区组成。在低速扩展区,峰时效态断口呈现冰糖状花样,在中速扩展区未看到长的疲劳条纹,仅发现个别细且短小的疲劳条纹,瞬断区可观察到二次裂纹、准解理和韧窝。
In this paper,the fatigue behavior of peak-aged 3J21 alloy was studied in material test system(MTS).The macro-fracture and micro-fracture were analyzed by scanning electron microscopy(SEM).The results show that the fatigue crack growth of peak-aged 3J21 alloys is mainly transgranular extension with a small percentage intergranular extension.The fatigue crack initiation life of peak-aged 3J21 alloy is shorter,the fatigue crack growth track is more straight,and the fatigue crack growth rate is larger.The fatigue crack growth resistance is smaller,so that the fatigue life is the shorter.The fatigue fracture consists of fatigue source,fatigue crack growth area and instantaneous fractured area.In low growing area,peak-aged fracture presents rock candy pattern,in middle growth area,the long fatigue striations are not found beside some small individual fatigue striations,and in stantaneous fault zone,two crack,quasi-cleavage and dimple could be observed.
出处
《材料开发与应用》
CAS
2012年第6期11-14,共4页
Development and Application of Materials
基金
国家自然科学基金资助项目(G1999065005)
关键词
J合金
峰时效
疲劳行为
裂纹扩展特性
3J21 alloy
Peak-aged
Fatigue behaviors
Crack growth characteristic
