高Fe、Si杂质含量的挤压铸造Al-Cu合金组织和力学性能研究  

Study on Microstructures and Mechanical Properties of Squeezing Casting Al-Cu Alloys with High Fe and Si Contents

作　　者：林波[1] 张卫文[2] 

机构地区：[1]贵州大学机械工程学院,贵州贵阳550025 [2]华南理工大学机械与汽车工程学院,广东广州510640

出　　处：《铸造》2015年第8期807-813,共7页Foundry

基　　金：贵州大学引进人才科研基金资助项目(201440);国家自然科学基金项目(51374110)

摘　　要：采用扫描电子显微镜、拉伸性能测试、定量金相、电子探针波谱分析、透射电子显微镜等技术研究了高Fe、Si杂质含量的挤压铸造Al-Cu合金的组织与力学性能。结果表明:随着杂质Fe和Si含量的增大,合金的力学性能下降,而伸长率下降得非常显著,这主要由于Fe、Si含量增大导致富铁相急剧增多、尺寸增大,合金中铸造缺陷的增多以及铝基体的增强相的减少。当挤压压力由0 MPa增大至75 MPa时,合金的力学性能得到显著的改善,尤其是合金的伸长率,这主要是由于压力导致的富铁相尺寸的细化,铸造缺陷的减少以及铝基体中增强相的增多。在挤压铸造75 MPa条件下,经过T5热处理后,杂质Fe和Si含量分别为0.5%时,铝铜合金的伸长率仍高达8.2%,此时依然保持较高的强度。The microstructures and mechanical properties of squeezing casting A1-Cu alloys with high Fe and Si contents were studied by scanning electron microscopy, tensile test, image analysis, EPMA, TEM. The results show that the mechanical properties decreased obviously with increase of the Fe and Si contents, especially the elongation, which was determined by the increased volume percent and size of iron-rich intermetallics, the increased cast defects and decreased volume fraction of precipitation particles in （A1） matrix. The mechanical properties improved obviously when the applied pressures increased from 0 to 75 MPa, especially the elongation, which was attributed to the refinement of iron-rich intermetallics, the reduction of cast defects and the increase of volume fraction of precipitation particles in （A1） matrix. After T5 heat treatment, the elongation level of 8.2 % and high strength was still obtained in the squeezing casting A1-Cu alloy （75 MPa） even when the Fe and Si contents was as high as 0.5 %.

关 键 词：挤压铸造 铝铜合金 富铁相 

分 类 号：TG146.21[一般工业技术—材料科学与工程]