Ceramic Particles Reinforced High Chromium Cast Iron Matrix Surface Composites Preparation And Wear Performance Of The Research

Ceramic particles locally reinforced high chromium cast iron matrix surface composites had been prepared successfully with liquid metal infiltration technology and fabrication of porous ceramic preforms, used A12O3, ZTA(ZrO2toughened A12O3) ceramic particles and high chromium cast iron as raw materials. The detailed process was:ceramic particles were plated nickel firstly, mixed the ceramic particles with agglutinant and put the mixture into a mould, then we got porous ceramic preforms after pressing and solidification. Riveted the preforms in sand mould, surface wearable composite cast was obtained by liquid metal penetrating porous ceramic performs.The wettability between Ni matrix alloy and ceramic was investigated, in the condition of1400°, the wetting and spreading of liquid Ni matrix alloy on A12O3, ZTA(25-30%ZrO2) and ZTA(55-60%ZrO2) ceramic was equilibrium in50seconds, the wetting angles were21°,17°and27°, respectively. The porosity of preforms with10%,20%and30%agglutinant was44.2%,42.3%and39.9%,respectively. The intensity of preforms increased as content of agglutinant increasing.The ceramic particles evenly embeded in high chromium cast iron matrix with no defect such as cavity, crack and so on; The volume fraction of ceramic particles in composites with the size of8-12mesh,12-20mesh and20-30mesh ceramic particles were55.1%,52.4%and47.0%respectively; EDS line scan on the interface between ceramic and matrix, showed that Ni matrix alloy had dissolved in high chromium cast iron matrix, ceramic and matrix had directly contacted. The plating had an important influence on wettability. The mechanism was:alloy element were adsorbed and accumulated in liquid metal surface, reduced the strain of liquid metal surface and the interface of solid-liquid, so as to got compact interface.The wearability of the composites was evaluated by three-body abrasive wear test, compared wearability of the composites with different component ceramic particles, the result was:the wearability of composites was better than high chromium cast iron, ZTA(55-60%ZrO2) reinforced composites was the best and5.9times higher than that of high chromium cast iron matrix, the next was ZTA(25-30%ZrO2) reinforced composites, Al2O3reinforced composites was the worst; Compared the wearability of composites with different size ceramic particles, the result was:8-12mesh ceramic particles reinforced composites was the best, the next was12-20mesh,20-30mesh was the worst; Analyzed the mechanism of three-body abrasive wear, the wearability of composites were closely related with the toughness of ceramic particles.