In-situ Synthesized WC Particles Reinforced Fe-based Wear Resistance Coating By Argon Arc Cladding With Tungsten Powder

Tungsten carbide （for short WC as fellow） particle is often used as anreinforcing phase of the wear-resistant material for high melting point, high hardness,good stability, and good wet ability with iron. Using surface cladding technologyfabricated WC particle reinforced iron-based composites on the parts surface toenhance wear resistance, can obtain good economic benefits. In this paper, in situsynthesized WC reinforced Fe-based composite was successfully fabricated, thealloys include W or WO₃, graphite, ferrosilicon, aluminum, and iron powder. Themicrostructure and wear behavior of the composite coating were investigated.Additionally, the effect of cladding parameters and carbon content on themicrostructure and property was studied.To fabricate the in-situ synthesized WC reinforced Fe-based composite, the keyfactor is choosing the suitable tungsten source. The experimental results showed thatthe composite perpetrated with WO₃powder contains Fe₃W₃C and austenite,but WCparticles has not been found, the hardness just reach HRC34.4, for the tungsten losscaused by the WO₃vaporization and splash. With W powder instead of WO₃astungsten source, the composite hardness can reach HRC67.8，for the in-situ WCparticles are uniformly distributed in the coatingTo improve the alloy liquid liquidity and surface forming, the aluminum isadded in the alloy powder. The result suggests that adding0.5wt%Al can obtain abetter affect. But, the surface forming poorer and quantity of WC particle decreasedwhen the1wt%Al is added. The main phases of coating were WC, Fe₃W₃C,martensite, Fe₃C, Al₄C₃,Fe₇C₃, residual austenite.Cladding process affects the phase composition and morphology of claddinglayer. When the cladding current control in150¹60A and the precast blockthickness is2².5mm, can obtain good forming cladding layer with slightly diluted.After multilayer cladding, the later layer can promote WC precipitation and grainrefinement in the previous cladding layer. As a result of increased carbon content,the WC quantity and size are increased, the Fe₃W₃C quantity decreased, andanti-cracking performance increased. The micro-hardness of the coating showsparabola distribution along thickness direction, and the micro-hardness rangedbetween HV0.21102.2and1863.5, the strengthen mechanism attributes to thesolution strength, refined crystalline strength, dispersion strength. Through contrastweight loss of abrasion after wet rubber friction wear test, cladding layerwear-resisting performance could be improved by more than19times, the wearmechanism of the coating attributes to the a slight micro-cutting with brittlenessshedding of the hard phase particles.