热处理对Mn-Cu合金微观组织和阻尼性能的影响

摘要

通过X射线衍射仪（XRD）、扫描电子显微镜（SEM）和动态机械热分析仪（DMA）的相结构、微观结构和阻尼性能的测试结果,研究了热处理工艺对轧制态CuMn50合金的微观组织和阻尼性能的影响。结果表明合金的阻尼性能随着应变振幅先缓慢增加而后迅速增加;随着冷速提高,Mn-Cu合金开始出现晶粒,阻尼性能降低,缓慢冷却有利于富锰区的产生,起到了时效的作用;炉冷时效后,阻尼性能进一步提高,时效时间对炉冷试样的微观结构和阻尼性能没有影响;水冷时效后,随着时效时间的增大,合金的晶粒先变得粗大随后析出第二相α-Mn,阻尼性能先增大到峰值随后略为减低,840℃固溶0.5h又420℃时效8h后,合金的阻尼性能达到最好。%The phase structures,microstructure and damping capacity of rolled CuMn50 alloy were tested using X-ray diffractometer,scanning electron microscopy and dynamic mechanical thermal analyzer.The effect of heat treatment on damping capacity and microstructure of rolled CuMn50 alloy was study.The result indicated that the damping capacity increased slowly at first and then increased rapidly with strain amplitude increasing.Manganese-copper alloy began to appear grains with the cooling rate increasing,and the damping capacity of rolled CuMn50 alloy decreased with the cooling rate increasing,the slow cooling rate is conducive to the production of manganese-rich,played a role in aging.After aged at 420℃ for different time,the damping capacity of furnace cooling specimens is further increased,however,aging time did not affect the damping properties of the sample.After aged at 420℃ for different time,with the aging time increases,the grain first becomes coarse,followed by precipitation of second phase α-Mn,and the damping capacity of water cooling specimens increased to the peak value first and then slightly reduced with the aging time increasing.When the aging temperature is about 420℃,the aging time is about 8h,the best damping capacity of water cooling specimens is obtained.