TiCp/Cr15高铬铸铁复合材料的制备与性能

以TiC_p粉末和水雾化Cr15高铬铸铁粉末为原料，采用粉末冶金液相烧结技术制备TiC_p增强高铬铸铁复合材料。研究了TiC_p含量对高铬铸铁的物相组成、显微组织和力学性能的影响。研究结果表明，全致密的TiC_p增强高铬铸铁基体复合材料的构成相为TiC、M₇C₃型碳化物、马氏体和少量奥氏体；随着TiC_p添加量增大，金属基体逐步呈孤岛状，并在其中析出越来越多的M₇C₃型碳化物，同时TiC_p逐步呈连续网状分布；同时，其硬度稳步提升，而抗弯强度和冲击韧性降低。当TiC_p添加量为20wt%时烧结态复合材料具有最佳综合力学性能。此时硬度为HRC 66.8 ，冲击韧性为6.86 J/cm2，抗弯强度为1 343.10 MPa。当TiC_p添加量为25wt%时硬度达到最大值HRC 67.20 。 

Preparation and properties of TiCp/Cr15 high chromium cast iron composites

TiC_p reinforced high chromium cast iron composites with full density have been fabricated by liquid phase sintering technology with water atomized Cr15 high chromium cast iron powders and TiC particles as raw materials. The effect of TiC content on the microstructure evolution, phase composition and mechanical properties was investigated systematically. The research results show that the composites consist of TiC, M₇C₃ type carbides, martensite and a small amount of austenite; With the increase of TiC_p addition, the metal matrix is gradually partitioned into island-like fragments, and M₇C₃ type carbides are principally precipitated in them. Hence continuous TiC particle network is formed step by step either. The composites’ hardness steadily increases at the same time, while both its bending strength and impact toughness decline. The sintered composite obtains its optimized mechanical quality as the TiC_p addition amount is 20wt%, that is hardness of HRC 66.8, the impact toughness of 6.86 J/cm2 and bending strength of 1343.10 MPa. Its hardness reaches the maximum value of HRC 67.20 while 25wt% TiC_p is added.