Abstract: Taking TiC as reinforcing particle and high chromium cast iron as matrix, the TiC_p/Fe test block and the back plate of a slurry pump were prepared by disappearing die casting technology, and the effects of particle size on hardness,relative wear resistance and impact toughness of TiC_p/Fe test block and back plate of slurry pump were studied. The results show that when the reinforcement particles are added to 1500 mesh, the hardness of the rear guard plate is increased by 55.4%,the relative wear resistance is 1.80 times of the matrix, and the impact toughness is 1.89 times of the matrix. The fracture mode of the reinforced particles changes from brittle fracture to massive fracture. The research results can provide reference for the production and application of TiC_p/Fe composites in lost foam casting.