摘要
承压杯安装在刹车壳体上,在使用过程中多个承压杯发生断裂。通过承对压杯外观观察,断口宏微观观察、能谱分析、金相组织检查、硬度检查、氢含量检测、有限元仿真模拟计算,并仿照承压杯的工作状况对完好承压杯进行了模拟试验。结果表明:承压杯的失效性质为镉脆开裂;承压杯失效原因为:工作环境经历较高的温度,在刹车过程中承压杯上表面导圆角处受到较大的拉应力,而承压杯表面采用了不适当的表面镀镉工艺,在这些因素的综合作用下承压杯发生镉脆开裂。故障发生的根本原因在于对承压杯的结构与受力考虑不充分。
Several bearing cups mounted on a braking shell of an aircraft braking unit cracked during service. Through macro and micro appearance observation, EDS analysis, metallurgical structure inspection, hardness and hydrogen content testing, FEA simulation and simulation test, the failure cause was analyzed. The results show that the cracking of the bearing cups was cadmium brittleness cracking. The failure took place under the co-effect of higher temperature service environment, bigger tensile stress near the round angle, and improper cadmium -plating process. The fundamental cause for this failure was inadequate consideration on the structure and stress of the bearing cups.
出处
《失效分析与预防》
2014年第5期289-294,共6页
Failure Analysis and Prevention
关键词
30CRMNSIA钢
承压杯
刹车壳体
沿晶断裂
解理断裂
镉脆
30CrMnSiA steel
bearing cup
braking shell
intergranular cracking
cleavage cracking
cadmium brittleness
