热处理对15%SiC_p/2009Al复合材料力学性能与断裂行为的影响

Effect of Heat Treatment on Mechanical Properties and Fracture Behavior of 15%SiC_p/2009Al Composite

使用不同固溶温度对粉末冶金工艺制备的15%SiCp/2009Al复合材料进行了处理,经过自然时效后进行了拉伸试验。结果表明:复合材料强度与塑性均随着固溶温度的提高而增加;挤压态的复合材料强度与基体合金基本相同。动态拉伸和断口形貌观察表明:挤压态的复合材料断裂形式为界面和基体中形成孔洞并相互连接导致试样断裂;而热处理后界面附近的基体中形成孔洞以及颗粒开裂并向基体中扩展导致试样断裂。

Solution treatments with different temperatures are conducted on 15%SiCp/2009Al composite followed by natural ageing. Tensile test results indicate that strength and elongation of composite are improved by increasing solution temperature while the strength of as-extruded composite is close to that of unreinforced alloy. Observation under dynamic tensile with fractograph shows that fracture for as-extruded specimens is composed of void nucleation on interface or matrix and mutual linkage, whereas the fracture after heat treatment is composed of void generation in matrix near interface and crack of particle followed by expansion into matrix for specimens.