Abstract
In this paper, we design a method that uses mechanical attrition to apply the electroless plating on the alloy surface, and compare the effect of electroless plating with that of traditional electroless plating. Based on the comparison results, we study the effects of mechanical attrition on the properties of electroless alloy plating during the electroless Ni-P plating. The results show that the mechanical attrition changes the growth pattern of Ni and P atoms in the traditional electroless plating. The resulting impact causes more energy to be transferred to the surface of the coating and brings plastic changes to the surface. The increase of the ion transport rate in the solution helps improve the uniformity of the coating. After mechanical attrition, the coating shows a very smooth and flat surface, indicating that this method effectively increases the coating density and at the same time saves a lot of coating resources. Mechanical attrition reduces the amorphism of the electroless coating so that the coating achieves the amorphous conversion from high to low energy. It can also make the zinc alloy coating harder and more resistant to corrosion. The surface of the magnesium alloy shows “cauliflower-like” structure. The “cauliflower” structure on the traditional electroless coating is not uniform, while the surface structure after the mechanical attrition is relatively smooth and flat, with tighter particle binding and no obvious pores. Amorphous Ni-P coating has an unstable mechanical shape in high temperature. Using the traditional chemical plating to coat the magnesium and zinc alloy can easily cause the coating to peel off or fail, while in the mechanical attrition method, the glass balls continuously impact the coating, increasing the atomic energy in the coating and inhibiting the galvanic corrosion between the coating and the magnesium alloy.
