Processing of ultra-high strength SiCp/Al–Zn–Mg–Cu composites

✍ Scribed by Wuhua Yuan; Jian Zhang; Chenchen Zhang; Zhenhua Chen

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 628 KB
• Volume: 209
• Category: Article
• ISSN: 0924-0136
• DOI: 10.1016/j.jmatprotec.2008.07.030

✦ Synopsis

The ultra-high strength SiC p /Al-10%Zn-3.6%Mg-1.8%Cu-0.36%Zr-0.15%Ni composite was prepared by spray co-deposition followed by extrusion process. The heat treatment processing, microstructures and mechanical properties of the as-processed composite were investigated. The well-bonded SiC/Al interfaces and fine grains of matrix alloy were obtained in the as-extruded composite. The precipitated phase MgZn 2 dissolved during solid solution treatment at 490 • C for 1 h, but the Cu-rich phase was residual in the matrix. Comparatively, the Cu-rich phase dissolved into the matrix alloy exposed at 470 • C for 1 h and then at 490 • C for 1 h. The composite heat-treated with 470 • C/1 h + 490 • C/1 h + 120 • C/28 h exhibited high modulus above 100 GPa and ultra-high strength about 785 MPa, which was 30 MPa higher than that of the same composite treated with 490 • C/1 h + 120 • C/28 h processing. The low elongation of the composite can be attributed to the breakage of SiC particulates and interfacial debonding of SiC/Al.