冷热循环对粉末冶金SiC_p/Al复合材料力学性能的影响  

Effect of Cooling-Thermal Cycling Treatment on Mechanical Properties of SiC_p/Al Composite Prepared by Power Metallurgy

作　　者：张琪[1] 樊建中[1] 肖伯律[1] 左涛[1] 

机构地区：[1]北京有色金属研究总院国家有色金属复合材料工程技术研究中心,北京100088

出　　处：《稀有金属》2007年第5期701-704,共4页Chinese Journal of Rare Metals

摘　　要：采用粉末冶金制备了15%(体积分数)SiCp/Al复合材料,研究了不同冷热循环工艺对复合材料力学性能的影响。结果表明,上限温度在175℃以下的冷热循环对复合材料的屈服强度和抗拉强度影响不大,当上限温度达到200℃后复合材料的屈服强度提高了80 MPa,抗拉强度则基本不变。复合材料的屈服强度的提高主要是由于材料在冷热循环的高温过程中基体中的G.P区转变成了过渡相θ″。断口观察表明,经过不同冷热循环工艺处理后,复合材料的断裂形式大致相同,即除了基体断裂外,还存在SiC颗粒开裂的情况。冷热循环对复合材料的延伸率影响不明显。15 % SiCp/Al composite billet was fabricated by power metallurgy method. The effect of different cooling-thermal treatments on the mechanical property of composites was investigated. The results showed that there was little influence on tensile strength when the superior limit of temperature of cooling-thermal cycling was below 175 ℃, however, σ0.2 was improved by 80 MPa and σb was not changed obviously when the superior limit of temperature of cooling-thermal cyclingwas 200 ℃. To composite, the improvement of σ0.2 was due to the transformation from G. P zones to θ＂ precipitates in the matrix during the high temperature process. Fractographic analysis revealed that the mode of composites fracture was similar, with a preference for failure in matrix and fracture of SiC particles. In addition, there was no obvious impact on the elongation of composites during cooling-thermal cycling treatment.

关 键 词：SICP/A1复合材料 冷热循环 强度 延伸率 

分 类 号：TG113.2[金属学及工艺—物理冶金]