Effect of laser remelting on the microstructure and properties of the aluminum high silicon alloy coating

An aluminum high silicon alloy coating with the composition of AlSi30Cu5 was prepared by the plasma spraying technology, and the coating was remelted by laser remelting process. The microstructure, mechanical properties and wear resistance of the coatings were systematically investigated. After the laser remelting, the defects of the sprayed coating were eliminated, the microstructure was dense and uniform, the porosity decreased from 3.66% to 0.37%, and the phases had not changed. The hardness and elastic modulus increased by 20.7% and 23.3% respectively, the fracture toughness increased by nearly 7 times, and the wear rate decreased by about 37.8%. Therefore, laser remelting can effectively improve the microstructure distribution and enhance the wear resistance of aluminum high silicon alloy coating.