| In this paper, a wear-resistant and high temperature oxidation-resistant of the infiltrated composite layer of WC/Ni, G/Ni, ZrO2/Ni and SiC/Ni were produced on the bronze surface through vacuum infiltration technique according to the work conditions of blast furnace. The microstructures, element distribution, phase, hardness of surface and cross-section, bending strength and wear-resistant have been investigated.The result shows that the infiltrated layer was composed of three layers, that is, surface composite layer, bond layer and diffusion layer because the composite material powder could melt and dissolve under the condition of elevated- temperature bronze liquid. The bonding strength can be enhanced owing to the existence of the diffused layer. Therefore the stress between the infiltrated layer and the substrate could be decreased. The distribution of strengthening grains was uniformity. The structure of infiltrated layer was soundness and the interface between the infiltrated layer and the substrate was excellent. The major phases of the infiltration layer were Ni-based solid solution, CrB, CrB2, Ni3B, Ni31Si12 and grain phases, which enhanced the wear resistance of the infiltrated layer. The elements distribution and hardness of the infiltrated composite layer was continuous and gradient from the surface to the substrate. The infiltrated layer uniformly incorporated at the interface between the matrix and particles.At the same time, the macro-hardness and micro-hardness of the infiltrated layer surface is up to HRC53 and HV1687, and the hardness presents gradient distribution. The peak hardness happened at the sub-surface of infiltrated layer. The three-point bending test shows that the displacement of infiltrated layer could cooperate with the substrate. The performance of the infiltrated layer is the best when the content of WC is 50%. The bending strength and tensile strength of the infiltrated layer is respectively up to 180MPa, 150MPa (the corresponding load and displacement respectively were 0.84KN and 0.7KN, 0.2mm and 0.25mm). The infiltrated layer was destroyed with partial collapse and surface crack. For G/Ni composite layer, the deformation of surface composite layer could accommodate with that of the substrate (the maximum load is 0.5KN for surface G/Ni layer with 5% G) when the displacement was less than 0.25 mm. the fracture strength of the ZrO2/Ni composite layer increases with the increasing content of ZrO2 (the maximum load is 0.65 KN for ZrO2/Ni composite layer with 25% ZrO2, and 0.4KN for ZrO2/Ni composite layer with 15% ZrO2). The deformation of surface composite layer could accommodate with that of the substrate when the displacement was less than 0.2 mm.The wear resistance of the infiltrated composite layer is increased obviously comparing with the substrate. Wear rate of Ni-based surface infiltrated layer and the substrate differ by two orders of magnitude (from 6.5×10-4 mm3/L, 9×10-4 mm3/L to 1.12×10-2mm3/L, 2.85×10-2mm3/L) under the load conditions of 200N, 300N and sliding velocity being 0.848 m/s. The softening of copper substrate resulted from the wear thermal, which resulted in the wear performance. Wear rate of the surface WC/Ni composite layer and the Ni-based infiltrated layer differ by one order of magnitude under the conditions of sliding velocity 0.848 m/s, load 300N (from 1.5×10-4mm3/L to 9.0×10-4mm3/L). The frictional coefficient and wear rate of the surface G/Ni infiltrated layer could not decrease effectively. The wear thermal resulted in the changing of wear circumstance. The graphite among the surface G/Ni infiltrated layer could reduce the fluctuation of the frictional coefficient and stabilize the frictional coefficient.The Ni-Si intermetallic compound and graphite came into being when the surface SiC/Ni composite layer was prepared on account of the reaction between the SiC and Ni. The fullerene structure on the SiC grain surface formed during the formation of the infiltrated layer, which strengthened the bonding strength between the grain SiC and the Ni. The graphite produced during the reaction could decrease the frictional coefficient.The melt bronze in capillary tube was looked as the analying unit. The result shows that the differential pressure of capillary tube, radius of capillary tube, viscosity of liquid metal and time of the bronze being at liquid condition are the major factors that affected the forming of the infiltrated layer. The forming process of the infiltrated layer can be divided into four levels. The first one is that the preform layer was heated by liquid metal. The second one is that the cooling liquid matel is remetled by later liquid matel. It leads to the forming of metallurgy layer. The third level is capillary effect which leads to the forming of surface fusion cladding. The fourth level is metallurgy sintering which lead to the forming of sinter layer.
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