原位自生20%TiC/Fe和20%(TiW)C/Fe复合材料的组织与性能

用原位自生法制备了20％TiC/Fe复合材料，并以W替代部分Ti制备了两种20％(TiW)C／Fe复合材料，研究了它们的显微组织与性能。结果表明：在20％TiC／Fe和20％(Ti0．8W0.2)C／Fe复合材料中，TiC和(TiW)C分别是两种材料中唯一的第二相，它们呈枝晶、方块和条形等多种形态。在20％TiC／Fe中．由于TiC与铁熔体的密度相差较大，出现了第二相的分布不均现象。在20％(Ti0.7W0.3)C／Fe复合材料中，(TiW)C相是唯一的第二相，它呈细小等轴粒状和条状两种形态，均匀分布于基体中，它的硬度与耐磨性明显好于前两种复合材料。

Microstructure and Properties of In-situ Synthesized 20%TiC/Fe and 20% (TiW)C/Fe Composites

The microstructural characteristics and properties of in-situ formed 20%TiC/Fe and two kinds of in-situ synthesized 20%(TiW)C/Fe composites in which part of Ti in TiC was substituted by W were investigated.The results show that in the TiC/Fe and(Ti_(0.8)W_(0.2))C/Fe composites,TiC and(TiW)C,as the only second phase respectively,assume many kinds of morphology,such as block,dendritic,rod-like and so on.And in the 20%TiC/Fe composite,there appears an inhomogeneous distribution of TiC in iron matrix due to the great difference in density between TiC and iron melt.In the 20%(Ti_(0.7)W_(0.3))C/Fe composite,in-situ formed(TiW)C reinforcements are homogeneously distributed in iron matrix and mainly in two kinds of morphology,i.e.finer spherulic and rod-like.Comparied with the 20%TiC/Fe and(Ti_(0.8)W_(0.2))C/Fe composites,the hardness and wear resistance of 20%(Ti_(0.7)W_(0.3))C/Fe composite are markedly increased.