论文部分内容阅读
对YG8和YG25两种WC-Co硬质合金不同时间深冷处理后的力学性能和疲劳性能进行了研究,利用X射线衍射方法分析了深冷前后合金的相变和残余应力变化,通过扫描电子显微镜(SEM)观察了材料的断口形貌和断裂方式。结果表明:深冷处理能有效提高了WC-Co硬质合金的硬度、强度、耐磨性和疲劳寿命。深冷处理时间是最主要的工艺参数,对YG8合金来说,2 h为深冷处理最佳工艺时间,而YG25则为8 h。其性能变化的主要原因是深冷处理导致硬质合金表面残余应力的变化和Co粘结相发生马氏体相变。
The mechanical properties and fatigue properties of YC8 and YG25 WC-Co cemented carbides after cryogenic treatment at different time were studied. The phase transformation and residual stress of the alloy before and after cryogenic treatment were analyzed by X-ray diffraction. (SEM) to observe the fracture morphology and fracture mode. The results show that the cryogenic treatment can effectively improve the hardness, strength, wear resistance and fatigue life of WC-Co cemented carbide. Cryogenic treatment time is the most important process parameters, for YG8 alloy, 2 h is the best cryogenic treatment time, while YG25 was 8 h. The main reason for the change is the change of residual stress on the cemented carbide surface caused by cryogenic treatment and the martensite transformation on the Co binder phase.