Au-Cr-Co-Zr合金性能与显微组织结构研究

摘要

The property and related microstructure of an Au - Cr - Co - Zr alloy in different conditions were studied by means of hardness test , X -ray diffraction (XRD) , scanning electron microscopic ( SEM ) observations and DTA analysis. The results show that second phase precipitates exist in casting condition and single phase solid solution is formed after high temperature solution treatment. The hardness increases strongly and higher after solution - aging than hardness - aging in generally. The electrical resistivity reduces strongly after aging in low temperature. It was revealed that the hardness increasing during the early stage is related to the transitional precipitaion along the grain boundary and the hardness decrease is caused by the stable second phase. The hardening mechanism of Au - Cr - Co - Zr alloy is solution strengthening.%通过硬度测试、X射线衍射(XRD)分析、扫描电镜(SEM)观察和差热分析(DTA),研究了Au - Cr - Co - Zr合金的显微组织结构和性能.研究表明,合金铸态存在析出相,高温退火后形成单相固溶体,固溶时效比应变时效硬度增加剧烈而且硬度普遍要高,时效后电阻率大幅下降.通过比较测试结果可知,在时效前期合金硬度的增加与在晶界处形成中间过渡相有关,合金的强化机制为固溶强化.