真空搅拌铸造制备SiC颗粒增强ADC12铝基复合材料及其力学性能表征

Preparation and Mechanical Properties of SiC Particulate-reinforced ADC12 Aluminum Matrix Composite by Vacuum Stir Casting

以SiC/Cu复合包裹粉体为增强相,采用真空搅拌铸造技术制备SiC/ADC12铝基复合材料,研究制备工艺条件对复合材料力学性能的影响,同时借助X射线衍射(XRD)和扫描电子显微镜(SEM)等测试分析手段对其物相结构进行表征。结果表明:SiC/Cu复合粉体显著改善了SiC颗粒在熔融铝合金基体中的润湿性和分散性。当搅拌温度为580℃,搅拌时间为30min,复合粉体添加量为4%(质量分数)时,复合材料获得最佳的力学性能,拉伸强度283MPa,硬度HB133,较基体合金分别提高24.1%和77.3%,较普通SiC增强复合材料提高15.5%和26.7%。

SiC/Cu composite powders were adopted to fabricate SiC particulate-reinforced ADC12 aluminum alloy matrix composite by vacuum stir casting technique,and the influence of preparation process on the mechanical properties of composite was investigated and optimized.The composites were characterized by X-ray diffractometry （XRD） and scanning electron microscopy （SEM）.The results show that dispersity and wetting ability of SiC particles in molten aluminum alloy matrix are significantly improved by SiC/Cu composite powders.At the condition of T=580℃,t=30min,and SiC content （w=4％）,the composite attains the best mechanical properties.Its tensile strength and hardness reach 283MPa and HB133,respectively,which are improved by 24.1％ and 77.3％,compared with ADC12 alloy matrix.It also shows obvious increase by 15.5％ in tensile strength and 26.7％ in hardness,respectively,compared to the composite with only bare SiC addition.