原位合成TiC/Cr19Al3钢结硬质合金组织与性能

Microstructure and performance of in situ synthesis TiC/Cr19Al3 steel bonded carbides

以钛铁粉、铬铁粉、铁粉、胶体石墨等为原料,原位反应合成了TiC/Cr19Al3钢结硬质合金,并用扫描电镜(SEM)、X射线衍射仪和洛氏硬度计等对所制备的试样进行了组织结构分析。结果表明,所反应合成的钢结硬质合金主要相组成为TiC+Fe-Cr固溶体,合成的硬质相TiC颗粒细小,随烧结温度升高TiC颗粒略有长大。当加入一定量的钼与硼后,钢结硬质合金致密度和硬度提高,TiC颗粒尺寸减小,分布更均匀。

TiC/Cr19Al3 steel bonded carbides were synthesized in situ by sintering compacts of mixed ferrotianium,ferrochromium,iron,and carbon powders.The microstructure of the steel bonded carbides was analyzed by scanning electron microscope,X-ray diffraction and Rockwell hardometer.The results show that the synthesized steel bonded carbides consist of fine TiC particles and Fe-Cr solid solution.TiC particles uniformly disperse in binder phase of the steel bonded carbides.The size of TiC particles increases with the increase of the sintering temperature.The addition of molybdenum and boron is beneficial to the densification and hardness of the steel bonded carbides,the refinement and the distribution uniformity of the TiC particles.