为探索提高SiCp/Fe力学性能的途径,采用包覆混料工艺,研究了该工艺对镀铜SiCp/Fe力学性能的影响,以及该工艺下增强粒子混合尺寸的影响.结果表明:包覆混料相比于普通混料,可显著改善SiC粒子在基体中分散的均匀性,而镀铜的作用是显著消除界面缺陷;性能的改善是包覆混料改善粒子分散性和镀铜改善界面结合的综合结果.对于体积分数30%SiCp/Fe的抗拉强度,通过包覆改善均匀性的贡献可提高7.2%,通过镀铜消除界面缺陷的贡献可提高12.5%,因此减少界面缺陷对颗粒增强复合材料力学性能的提高更重要.混合尺寸粒子对力学性能的增强效果明显高于其对应单一尺寸,这是由于小尺寸粒子能有效地提高基体的强度,而大尺寸颗粒更有效地承担载荷传递的作用.
To improve the mechanical properties of the SiCp/Fe composites, the effect of high?energy ball milling processing on the mechanical properties of copper?coated SiC particles reinforced iron matrix composites were investigated, and the effect of size mixture of copper?coated SiC particles on the properties of the composites was discussed as well. The results shows that the properties of composites have been improved by the high?energy ball milling that can also improve the uniformity of SiC particles distribution in the composites. The copper coating on the SiC particle surface can reduce the interfacial defects of the composites which is helpful for the improvement of mechanical properties of the composites. The tensile strength of the composites is increased by 7. 2% because of the uniformity of SiC particles distribution and by 12. 5% because of the reducing of interfacial defects which is more evident. The mechanical property of the composites reinforced by the mixture?sized SiC particles was higher than that of the composites reinforced by the related single?sized particles because the smaller?sized SiC particles tend to improve the strength of the matrix and the larger?sized SiC particles carry and transfer more load.