复合变质对AlSi7Mg合金组织和性能的影响  

The Effect of Compound Modification on the Mechanical Properties and Microstructure in AlSi7Mg Casting Alloy

作　　者：张冀粤[1] 王智民[1] 黄积荣[1] 

机构地区：[1]西安理工大学

出　　处：《特种铸造及有色合金》1999年第4期6-8,共3页Special Casting & Nonferrous Alloys

摘　　要：通过在铸造ＡｌＳｉ７Ｍｇ合金中加入一种新型复合变质剂，研究其对合金力学性能和组织的影响，并采用透射电子显微镜（ＴＥＭ）研究合金在时效过程中组织的变化。结果表明：采用此新型变质剂可有效提高铸造ＡｌＳｉ７Ｍｇ合金的力学性能。合金经５３５℃×６ｈ固溶化处理和１５０℃×６ｈ时效处理后，其σｂ达到３５１．７ＭＰａ，δ达７．７９％。经ＴＥＭ分析，采用此变质剂处理的铸造ＡｌＳｉ７Ｍｇ合金在时效过程中不仅会产生Ｍｇ２Ｓｉ相，而且发现了一种新的时效强化相。通过分析，认为该相的析出过程与Ｍｇ２Ｓｉ相似，且其析出温度要较Ｍｇ２Ｓｉ相略低。由于此新强化相的析出使得合金在较低温度时效时即可获得较好的强化效果。The influence of modification treated with a new compound modifier on mechanical properties and microstructure of AlSi7Mg alloy has been investigated.The change of microstructure during aging treatment has been studied by means of TEM.The results show that the new modifier can increase the mechanical properties of AlSi7Mg alloy with the ultimate tensile strength 351.7 MPa and the elongation 7.79% after 6 hours solution treatment at 535 ℃ and 6 hours aging treatment at 150 ℃.The TEM analysis shows that during aging treatment not only Mg 2Si phase but also a new reinforced phase are precipitated in modified AlSi7Mg alloy.It is considered that the pricipitation process of the new phase is similar to that of Mg 2Si phase and lower in the pricipitating temperature.Therefore the AlSi7Mg alloy both the higher strength and elongation at T 5 treatment.

关 键 词：ALSI7MG合金 组织 力学性能 复合变质剂 铝合金 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG292[金属学及工艺—金属材料]