The Wear Properties of TiC/Al-Based Composite Coating Applied by Laser Cladding

Aluminum powders with different concentrations of TiC ceramic particles were applied to an AZ31B magnesium alloy by laser cladding. Due to differences in coefficients of thermal expansion, the distribution of TiC ceramic particles in the cladding layer was not uniform. The results show that the degree of TiC ceramic particle agglomeration in the cladding layer increases with increasing TiC content. The phases of cladding metal mainly consisted of Al, γ-Al12Mg17, β-Al3Mg2, and TiC. The γ-Al12Mg17 phase mainly distributed to the bottom of the cladding layer, and the β-Al3Mg2 phase distributed to the middle and surface areas. The existence of the γ-Al12Mg17 phase enhanced the hardness of the fusion zone. The microhardness of the cladding layer increased with increasing TiC ceramic particle content. An appropriate TiC content improved the wear resistance of the cladding layer. When the TiC content was excessive, the agglomeration behavior of TiC ceramic particles strongly affected the wear resistance of the coatings.