添加Cu对SiCp/Al-Si复合材料组织与性能的影响

利用X射线衍射仪、扫描电镜、电子天平、力学性能试验机等研究了Cu元素含量对粉末冶金法制备的SiC_p/Al-Si复合材料组织与性能的影响。结果表明:添加Cu元素后,材料的致密度、硬度、抗拉强度及耐摩擦磨损性能都获得了较大的提高,且强度在Cu含量为4%(质量分数)时达到最大值。由于在基体中以铜粉的形式添加Cu元素时,较低温度下即可在Al-Cu边界通过互扩散形成液相,从而填充基体及界面处的缝隙、孔洞等缺陷;并且在压坯快速冷却到室温的过程中,生成的α-Al和Al₂Cu相均对材料有强化作用,使得复合材料的综合力学性能获得提高。

Effect of Cu addition on microstructure and properties of SiC p/Al-Si composites

Influence of different content of Cu addition on microstructure and properties of the SiC_p/Al-Si composites prepared by powder metallurgy was studied by means of X-ray diffraction, scanning electron microscopy, precision electronic balance and universal testing machine. The results show that the addition of Cu element leads that the density, hardness, tensile strength, friction and wear resistance of the material are improved greatly, and the strength reaches the maximum when the Cu content is 4% (mass fraction). Since the Cu element is added in the form of copper powder in the matrix, a liquid phase can be formed through mutual diffusion at the Al-Cu boundary even at a lower temperature, thereby filling the gaps, holes and other defects in the matrix and at the interface. During rapid cooling of the green compact to room temperature, α-Al and Al₂Cu phases are produced and both have strengthening effect on material, which improves the comprehensive mechanical properties of the SiC_p/Al-Si composites.