锶变质时间对近共晶铝合金电力金具材料组织与性能的影响  

Effect of Sr Modification Time on Microstructure and Properties of Near Eutectic Aluminum Alloy Electric Power Fitting Materials

作　　者：李捷[1] 张军 LI Jie;ZHANG Jun(State Grid Beijing Electric Power Company,Beijing 100031,China;China Electric Power Research Institute,Beijing 100055,China)

机构地区：[1]国网北京市电力公司,北京100031 [2]中国电力科学研究院有限公司,北京100055

出　　处：《铸造技术》2020年第10期913-915,929,共4页Foundry Technology

摘　　要：在近共晶成分Al-Si-Mg合金中,加人锶(Sr)作为变质剂,研究变质时间对合金组织与性能的影响。结果表明,Sr能使共晶硅在铸态时呈团絮状,热处理后颗粒状的组织更细小。但是,随变质时间的延长,镁(Mg)、Sr含量会逐渐烧损,导致强化效果与变质效果削减,力学性能也随之降低,当变质时间为1h时,合金的综合力学性能最好,此时,其抗拉强度为325.6MPa,伸长率为8.3%。In the near-eutectic Al-Si-Mg alloy,Strontian(Sr)was added as a modifier.The effect of Sr modification time on the microstructure and mechanical properties of the alloys were studied.The results show that Sr can make the eutectic silicon become flocculent in the as-cast state,and the particle microstructure became finer after heat treatment.However,with the increasing modification time,the content of Magnesium(Mg)and Sr was burning lost gradually,which caused the effect of strengthening and modification decreased,so did mechanical properties.The best comprehensive mechanical properties of the alloy were observed after being modified for an hour,which the tensile strength is 325.6 MPa and the elongation is 8.3%.

关 键 词：Sr变质时间 近共晶Al-Si合金 电力金具材料 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG113[金属学及工艺—金属材料]