变速器拨叉用过共晶铝硅合金压铸性能研究  

Research on Die Casting Performance of Hypereutectic Al-Si Alloy Used in Transmission Fork

作　　者：陆从相[1] 周鹏飞[1] 李天景[1] 

机构地区：[1]盐城工业职业技术学院汽车工程学院,江苏盐城224005

出　　处：《铸造》2017年第12期1279-1282,1286,共5页Foundry

摘　　要：以Al-17Si-4.5Cu-0.5Mg合金为原料,分析了自动变速箱用换挡拨叉压铸件的组织和性能。通过对压铸件不同部位的组织观察、断口形貌分析及能谱检测得出:压铸件Si相大小约40~60μm;组织中存在富Cu相及针状Fe相;断口处没有典型的韧窝特征,出现可见粗大第二相,破碎的Si相,断裂方式属于脆性断裂;合金断口由裂纹发展导致,裂纹附近的Si颗粒出现明显裂纹和破碎。Al-17Si-4.5Cu-0.5Mg alloy as raw materials, the structure and performance of the automatic transmission gear shift fork by die casting were analyzed. The observation results of the different parts of the sample show that the size of Si phase is about 40-60 μm; Cu-rich phase and needle-like Fe phase exist in the structure; and the fracture has no typical dimple features, also appears visible coarse second phase and broken Si phase, the style of fracture is brittle fracture; alloy fracture was resulted from the crack extension, Si particles near the crack appear obvious cracks and broken.

关 键 词：Al—17Si-4.5Cu-0.5Mg 压铸 SI相 组织 断裂 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG249.2[金属学及工艺—金属材料]