【摘要】 为减少熔炼时合金元素的烧损,采用真空感应熔炼工艺制备了低铬铜铬合金。通过扫描电镜、光学显微镜和能谱分析等手段,研究了真空环境下不同浇注工艺对合金铸锭组织、缩孔及成分偏析的影响.研究结果表明:利用真空直接加铬炼制低铬铜铬合金,采用合适的熔炼和浇注工艺,可以较精确控制合金成分;在低的浇注温度和大冷却速度下可以获得几乎无宏观偏析,铸造缺陷很少的铜铬合金铸件;铸件500℃退火3 h后,硬度可达141HV,电导率提高到86%IACS.更多还原

【Abstract】 Vacuum induction melting was used to prepare a Cu-Cr(Cu-0.8wt.%Cr) alloy in order to reduce heat loss of Cu,Cr in the melt.The effect of different casting processes on the microstructures and properties of Cu-Cr alloy were studied by OM,SEM and EDS.The results showed that the alloy composition could be accurately controlled using suitable vacuum melting and pouring processes with direct addition of chromium.Alloy ingots with little macro segregation and casting defects could be prepared under low pouring temperature and high cooling rate.The microhardness and electrical conductivity of the ingots arrived at 141HV and 86%IACS respectively after being annealed at 500 ℃ for 3 h.更多还原