制冷压缩机阀片断裂失效分析

对半封闭活塞式制冷压缩机的断裂阀片的分析表明,阀片失效属于金属疲劳断裂机制。阀片表面缺陷可以形成疲劳裂纹源,而阀片在加工或者使用过程中形成的机械损伤或者腐蚀凹痕是表面缺陷的表现形式。对7C27 Mo2和20C两种阀片钢进行比较分析可知,7C27 Mo2比20C具有更高的抗拉强度、硬度、疲劳强度和耐腐蚀性,在压缩机高负荷使用条件下应优先选用7C27 Mo2。

Analysis of fracture valve failure in refrigeration compressor

Through the analysis of fracture valves of the semi-hermetic refrigeration compressor,it indicates that the valve failure is classified as metal fatigue fracture mecha- nism. The valve＇s surface defects,including mechanical damage or corrosion pits which are emerged in the processing or use of the valve, may cause fatigue crack originals. By compa- ring two valve materials of 7C27Mo2 and 20C,it is found that 7C27Mo2 has a higher ten- sile strength,hardness, fatigue strength and corrosion resistance. Under the conditions of the high-load operation of the compressor,it is suggested to choose 7C27Mo2 as first.