深冷处理对钴基合金摩擦磨损性能的影响

Effect of Cryogenic Treatment on Friction and Wear Properties of Cobalt-based Alloy

将K6509钴基合金样品在-196℃液氮中深冷4~44 h,通过金相分析、硬度分析等技术手段研究深冷处理后微观结构以及力学性能的变化情况,对深冷后的钴基合金样品进行直线往复式摩擦磨损实验,研究其摩擦因数和磨损率的变化情况。试验结果表明,随着深冷时间的延长,硬度基本呈逐渐提高趋势,深冷44 h后硬度达到最高,较未深冷样品提高了23.6%,通过摩擦磨损试验研究,发现经深冷后的钴基合金样品的摩擦因数曲线变得较为平稳,平均摩擦因数明显降低,其中DCT36钴基合金样品摩擦因数最为平稳,并达到最低的摩擦因数,磨损率随着深冷时间的延长先提高后降低,其中DCT28钴基合金样品磨损率达到最高,在加载载荷为3 N、4 N、5 N的工况下磨损率分别提高了57.91%、44.29%、27%。

K6509 cobalt-based alloy samples were cryogenically cooled in liquid nitrogen at-196℃for 4-44 hours.The microstructure and hardness analysis were used to investigate the changes in microstructure and mechanical properties after cryogenic treatment,and friction coefficient and wear rate via linear reciprocating friction and wear experiment.The experimental results show that the hardness basically increased gradually with the increasing of cryogenic time.The hardness increased by 23.6%reaching the highest after 44 h.The friction coefficient curve of the cobalt-based alloy sample becomes relatively stable,and the average friction coefficient is significantly reduced after deep cooling,and the friction coefficient curve of DCT36 sample was the most stable with the lowest average friction coefficient.The wear rate increased firstly and then decreased with the increasing of cryogenic time.The wear rate of DCT28 sample reached the highest,and the wear rate increased by 57.91%,44.29%,27%.