摘要
采用真空热压烧结工艺制备Al-30Si合金、30%Sip/Al、30%SiCp/2024Al、30%SiCp/6061Al(均为体积分数)复合材料,测定其热膨胀系数及力学性能。利用扫描电镜(SEM)、能谱仪(EDS)对其微观组织结构及断口形貌进行表征,探究了高硅铝合金及颗粒增强铝基复合材料的组织与性能,分析了材料的断裂机制。结果表明:SiCp/2024Al复合材料中SiC颗粒分布均匀,组织致密,综合性能好,热膨胀系数(CTE)为13.69×10-6/K,硬度达到134 HB,极限抗拉强度达353 MPa。SiCp/6061Al复合材料中SiC颗粒分布较均匀,界面结合较好,组织不够致密,有少许孔隙,性能较好。SiCp/6061Al和SiCp/2024Al复合材料的断裂方式都是界面基体的撕裂结合SiC颗粒的断裂。Sip/Al复合材料中Si颗粒分布较均匀,断裂方式为界面脱开,性能较差。Al-30Si合金在烧结过程中形成大量板条状的Si相,性能最差,断裂方式以合金撕裂为主。
Al-30Si alloy, 30%Sip/Al, 30%SiCp/2024Al and 30%SiCp/6061Al composite materials were produced by vacuum hot pressing sintering process. The coefficient of thermal expansion and mechanical properties of the composites were investigated. The microstructure and fracture appearance were characterized with SEM and EDS. The microstructure, mechanical properties and the fracture mechanism of high silicon aluminum alloy and particle reinforced aluminum matrix composites were explored. The results show that the SiC particles are evenly distributed in the 2024 aluminum matrix, the composite is compact and has the best properties. The coefficient of thermal expansion, hardness and the ultimate tensile strength of the composite are 13.69×10^-6/K, 134 HB and 353 MPa, respectively. There are a few pores in the SiCp/6061Al composite, the sintered density and uniformity of the composite are worse than SiCp/2024Al composite. The fracture modes of SiCp/6061A1 and SiCp/2024Al composites are both tearing of interface matrix combined with breakage of SiC particles. Si particles are evenly distributed in the Sip/Al composite, the fracture mode of the composite is interface declutch, leading to poor performance. A large number of lath-shaped Si phase form in the Al-30Si alloy during the process of sintering, leading to the worst performance of the material.
出处
《粉末冶金工业》
CAS
北大核心
2014年第4期45-49,共5页
Powder Metallurgy Industry
基金
国家自然科学基金(51371077)
关键词
铝基复合材料
断裂
微观组织
力学性能
aluminum matrix composite
fracture
microstructure
mechanical property
作者简介
作者简介：柳培（1991-），男（汉），硕士研究生，主要从事铝基复合材料的研究。
