使用不同粒度的铁粉,采用电流直加热动态热压烧结工艺制备了10%(体积分数)的SiC颗粒增强铁基复合材料,研究了铁粉与SiC粒子颗粒级配对复合材料显微组织和力学性能的影响.结果表明,SiC粒子与铁粉的颗粒级配,显著影响复合材料基体中增强粒子的分布状况和力学性能.建立了粒子分布的双基体颗粒级配模型,只有铁粉中一次颗粒与二次颗粒的粒径比为6.5、二次颗粒含量为4.6%、铁粉一次颗粒与SiC的粒度比值为15.9时,SiC颗粒才能很好地填充铁粉间隙并均匀地分布在基体中,复合材料将具有较高的力学性能.模型计算的结果和实验结果相符合.
10% SiCp/Fe composites were fabricated by means of specimen current heating dynamic hot press sintering with iron powder with different sizes. The results demonstrate that the iron powder size has great influence on the distribution of SiC particulates in the composite, and therefore on the mechanical properties. A model, considering iron powder as the mixture of two sorts of particles with different sizes, is suggested based on the results. The modeling shows that only the size ratios of coarse iron powder to fine powder, and to reinforcing particles are 6.5 and 15.9 respectively, and the content of fine powder is 4.6%, an even reinforcing particle distribution can be realized to produce good properties of composites. The modeling is agreed with experiments well.