Wear is one of the three major failure modes (wear, corrosion and fracture) of metal mechanical parts. Modern industry urgently needs workpieces that can work effectively under severe wear conditions (such as high temperature, high speed friction and wear, etc.). Compared with traditional metal abrasion resistant materials, ceramic particle reinforced metal matrix surface composites effectively combine the high strength and toughness of metal materials with the high hardness of ceramic particles to form a high-performance material with overall impact resistance and surface abrasion resistance, which has attracted extensive attention. Among them, tungsten carbide particle reinforced steel matrix surface composite has the advantages of price, performance and technology. This paper reviews the research and application of tungsten carbide particle reinforced steel-based wear-resistant composites at home and abroad. Tungsten carbide (WC) is hexagonal crystal, with high hardness, high melting point, small thermal expansion coefficient, good wear resistance, and so on. Moreover, the wetting Angle of the liquid iron and steel encapsulates the tungsten carbide particles, which can support and protect the tungsten carbide particles. Almost all steel materials can be used as the matrix of casttungsten carbide reinforced particles due to the good forming properties of molten steel and complete wetting of tungsten carbide particles. However, the specific choice of steel or iron matrix should be based on the corresponding operating conditions (temperature, stress, wear resistance, etc.) to choose.

At the same time, tungsten carbide granule reinforced local composite material of steel matrix was designed and prepared. Low chromium cast iron, nodular cast iron, cast steel, gray cast iron and other steel materials were selected as bulk materials to study their composite effect. The composite process and casting process were improved and optimized, and were applied to the local composite of the worn surface of the flow parts of slurry pump. The microstructure and formation mechanism of the composite layer were analyzed, and the erosion wear properties of the composite material were investigated and compared with that of high chromium cast iron (Cr15Mo2).

It turns outthat the water glass sand mold (core) plus negative die casting infiltration technology can achieve complex surface (surface) the preparation of particle reinforced composites, pouring method is simple and reliable, in less than 10 mm, base material thickness of composite layer thickness can reach 3 ~ 7 mm, and the composite layer less casting defects, the composite effect is good, high density and interface bonding strength, material organization is divided into the base material area, transition area and complex area, uniform distribution in composite layer of tungsten carbide particles in high chromium cast iron substrate and grain shape intact. The pump chamber and inner cover of the 4' slurry pump produced by the module compaction pulverization process have basically realized the local composite of the whole worn surface. Grey cast iron with low chromium cast iron casting temperature is 1550~ 1600degreescan get composite good surface composite material, relatively ideal effect.

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