Sr和P变质对Mg-5Sn-2Si合金显微组织的影响  

Effect of Sr and P Modification on Microstructure of Mg-5Sn-2Si Alloy

作　　者：周庆标 崔红保[1] ZHOU Qing-biao;CUI Hong-bao(School of Material Science and Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China)

机构地区：[1]河南理工大学材料科学与工程学院,河南焦作454000

出　　处：《铸造》2020年第5期456-460,共5页Foundry

基　　金：国家自然科学基金(51571086,51271073)。

摘　　要：利用Sr、P及Sr与P复合添加分别对Mg-5Sn-2Si合金进行变质处理,研究了不同Sr含量。不同P含量以及Sr和P复合添加对Mg2Si变质效果的影响。结果表明:随着Sr含量的增加,共晶Mg2Si相的形貌逐渐由汉字状向蠕虫状和颗粒状转变,共晶Mg2Si显著细化,但对初生Mg2Si相钝化作用有限。在Mg-5Sn-2Si合金中添加P后,P和熔体Mg形成Mg3P2,对初生Mg2Si起到形核核心作用,从而细化初生Mg2Si,而对细化共晶Mg2Si相作用不大。P和Sr复合变质后,初晶Mg2Si尺寸相对单一P变质效果更细小,P和Sr复合变质对合金中的初生Mg2Si和共晶Mg2Si具有更好的细化作用。The effects of P and Sr additions on the primary and eutectic phases in Mg-5Sn-2Si alloy were studied.The refined Mg2Si phase was observed and the refinement mechanism of the primary Mg2Si and coarse Chinese script eutectic Mg2Si was analyzed.The results show that the coarse Chinese script eutectic Mg2Si phase were transformed into vermicular and granular Mg2Si phase with the addition of Sr and primary Mg2Si was also refined,but the edges and corners of primary Mg2Si phase were still sharp.Primary Mg2Si could be refined by the Mg3P2 which was formed with the addition of P into Mg melt.But there was small effect on the refinement of eutectic Mg2Si.After P and Sr combined modification,the size of primary Mg2Si is smaller than that of single P modification,and P and Sr combined modification has better refining effect on primary Mg2Si and eutectic Mg2Si in the alloy.

关 键 词：Mg-5Sn-2Si合金 锶和磷 显微组织 复合变质 

分 类 号：TG146.2[一般工业技术—材料科学与工程]