机械合金化法制备(Ag-Cu28)-xSn合金的结构和性能研究

利用机械合金化法制备(Ag-Cu28)-xSn系合金粉末,借助差示扫描量热仪、X-射线衍射仪、扫描电镜等,研究了Sn含量对合金熔化温度、球磨时间对合金粉末的物相组成及显微结构的影响。研究表明:Sn对合金的熔化温度有显著影响,随Sn含量增加合金熔化温度下降趋势减缓;当Sn含量为30%时,合金熔化温度最低为539.3℃。球磨40 h时,(Ag-Cu28)-30Sn粉料合金化完全,其物相组成为Ag4Sn、Cu3Sn和Cu6Sn5。球磨初始阶段(Ag-Cu28)-30Sn粉料颗粒异常长大,球磨至40 h时合金化完成,颗粒断裂和焊合达到平衡,合金粉末粒度均匀,平均粒径约为5~10μm。

Study on Microstructures and Properties of (Ag-Cu28)-xSn Alloys by Mechanical Alloying

(Ag-Cu28)-xSn alloy powders were prepared by mechanical alloying(MA).The effects of tin contents on melting temperatures,phase compositions and microstructures of alloy powders with different milling time were studied by XRD,DSC and SEM.The results show that the melting temperatures of alloys can be reduced effectively with tin contents increasing.The lowest melting temperature of alloy powders is 539.3℃ when tin content is 30%.As milling time is 40 h,the alloying process of(Ag-Cu28)-30Sn alloy is completed and the phase compositions of(Ag-Cu28)-30Sn alloy include of Ag4Sn,Cu3Sn and Cu6Sn5.The particle size grows abnormality at the preliminary stage of ball milled.As the alloying process is completed,the balance is got between the rate of welding and the rate of fracturing,the particle size is no longer refined.The averaged particle size of(Ag-Cu28)-30Sn powders has a distribution from 5 μm to 10 μm when milling time is 40 h.