铸造Al-Si-Cu-Mg合金分级热处理工艺及对力学性能的影响  

Multi-stage Heat Treatment Process and Effect on the Mechanical Properties of Cast Al-7.0%Si-2.5%Cu-0.5%Mg Alloy

作　　者：张伟[1] 杨通[1] 李建平[1] 李高宏[1] 夏峰[1] 郭永春[1] 

机构地区：[1]西安工业大学材料与化工学院,陕西西安710032

出　　处：《铸造技术》2007年第12期1631-1635,共5页Foundry Technology

基　　金：总装备部研究项目(ZLY2006356)

摘　　要：通过示差热分析及对Al-7.0Si-2.5Cu-0.5Mg合金热处理工艺参数的研究发现:为了防止合金中低熔点共晶物在固溶处理过程中熔化,同时提高Q、Al2Cu等相在合金中的溶解度,应选择分级固溶的方式进行。一级固溶在500℃固溶3h后,可使合金中低熔点共晶物完全溶解,此时合金的熔点为540℃;综合各因素,该合金较好的热处理工艺为:500℃×3h、530℃×14h;175℃×6h,此时,合金的力学性能可以达到:σb≥385MPa,δ5≥5.0%。Multi-stage heat treatment and mechanical properties of cast Al-7.0Si-2.5Cu-0.5Mg alloy were studied using combination methods of Differential Scanning Calorimeter （DSC） analysis, hardening curves measurement and tensile test. The results show that in order to prevent the low melting point eutectics in the alloy from fusing during solution treatment process, and to raise the solubility of alloying phases Q and Al2Cu, the multi-stage solution treatment should be given. After being treated at 500℃ for 3 hours, the low melting point eutectics in the alloy were fully dissolved and the alloy will be fused at 540℃. Based on an overall consideration, two-stage heat treatment process for the alloy was carried out as following： solution at 500 ℃ for 3 h, following with 530 ℃ for 14 h, then quenching and then ageing at 175℃ for 6 h. The room temperature ultimate tensile strength σb≥385 MPa and elongation δ5≥5. 0% can be obtained under this two stages heat treatment.

关 键 词：铸造铝合金 分级热处理 力学性能 

分 类 号：TG166.3[金属学及工艺—热处理]