热处理对热等静压SiP/Al-Cu复合材料显微组织和力学性能的影响

采用元素粉作为原料, 通过热等静压技术(HIP)制备出50%Si_P/Al-Cu和70%Si_P/Al-Cu(体积分数)复合材料, 研究固溶处理和峰值时效处理对复合材料显微组织、 Al₂Cu相溶解过程及力学性能的影响。结果表明: 热等静压技术制备的Si_P/Al-Cu复合材料完全致密, 组织均匀细小, 材料由Si相、 Al相和Al₂Cu组成, 白色Al₂Cu相产生于原始的Cu粉与Al粉界面处。在516 ℃固溶处理2 h后, 70%Si_P/Al-Cu复合材料中的Al₂Cu相全部溶入Al基体中, 而50%Si_P/Al-Cu复合材料中还残留少量Al₂Cu相。经过峰值时效处理后, 50%Si_P/Al-Cu和70%Si_P/Al-Cu复合材料的抗弯强度为548 MPa和404 MPa, 相对于热等静压态分别提高了38.81%和13.51%, 复合材料的强度显著增强。

Effect of heat treatment on microstructure and properties of SiP/Al-Cu composites prepared by HIP

50%Si_P/Al-Cu and 70%Si_P/Al-Cu composites were prepared by hot isostatic pressing(HIP) method using pure elemental powders. The microstructure evolution and dissolution of Al₂Cu were studied. The properties of as-hot isostatic pressed composites before and after heat treatment were also investigated. The results show that the prepared Si_P/Al-Cu composites are fully dense. The silicon particles well distribute in Al matrix and still keep the original size. The presence of Al₂Cu, Si and Al is identified in the as-hot isostatic pressed composites. The Al₂Cu phase is formed in the boundaries of the Cu and Al particles. After solution treatment, Al₂Cu phase dissolves into the 70%Si_P/Al-Cu composites, however, some Al₂Cu phase does not dissolve into the matrix of 50%Si_P/Al-Cu composites completely. After the peak-aged treatment, the bending strength of 50%Si_P/Al-Cu and 70%Si_P/Al-Cu composites as-peak-aged is 548 MPa and 404 MPa, which is increased by 38.81% and 13.51% compared with that of as-hot isostatic pressed, the three points bending of the composites can be improved remarkably.