Composite coating on surface of magnesium alloy structural component and preparation method of composite coating

Abstract

The invention discloses a composite coating on the surface of a magnesium alloy structural component. The composite coating comprises a matrix bonding layer and a surface wear-resistant layer, wherein the matrix bonding layer is a nitrogen ion implantation layer or an oxygen ion implantation layer; the surface wear-resistant layer is a laser cladding SiC layer, a laser cladding SiO2 layer or a laser cladding SiC and SiO2 composition layer; the ion implantation bonding layer is combined with a magnesium alloy matrix; and the surface wear-resistant layer is combined with the ion implantation bonding layer. The invention also discloses a method for preparing the composite coating. The method comprises the following steps: preparing a matrix bonding layer on the surface of a magnesium alloy matrix in situ by adopting an ion implantation technology; and preparing a surface wear-resistant layer on the matrix bonding layer by adopting a laser cladding method. The magnesium alloy coating prepared by a method disclosed by the invention is tightly combined with the matrix, is excellent in corrosion resistance and wear resistance, flat and dense in surface, uniform in interface transition and small in strain-strain gradient and is not damaged under the action of an alternating load.

Description

technical field [0001] The invention belongs to the field of magnesium alloys, and relates to a magnesium alloy coating, in particular to a method for preparing a composite coating on the surface of a 3D printed magnesium alloy device. Background technique [0002] Magnesium alloys have excellent comprehensive performance and are widely used. However, magnesium alloys have active chemical properties and are prone to corrosion failure in humid environments. In addition, magnesium alloys have low hardness and are prone to surface wear and damage during friction; this leads to magnesium alloy parts being only It is used in a low-corrosion non-moving environment, but cannot be applied to a high-corrosion and high-wear working environment. Therefore, how to solve the problem of abrasion and wear failure on the surface of magnesium alloy structural parts has become a key technical problem in current industrial applications. [0003] Aiming at the "corrosion failure" problem of ma...

AI Technical Summary

Problems solved by technology

Aiming at the "wear damage" problem of magnesium alloys, micro-arc oxidation and vapor deposition techniques are generally used to prepare hard alloy layers or ceramic layers on the surface of magnesium alloys. Although this method can significantly improve the bearing capacity and wear resistance of magnesium alloy surfaces , but due to the large difference between the mechanical properties of the ceramic reinforced layer and the matrix, there is a strain-strain gradient at the interface. When the load is applied, the substrate will undergo plastic deformation. The shear stress-strain of the interface, when the plastic shear strain at the interface is higher than the critical value, will generate cracks or adhesive wear failure at the interface

[0004] To sum up, current protective coatings on the surface of magnesium alloys mostly focus on the research of single corrosion or wear performance. Wear-resistant and corrosion-resistant functional requirements of components

Images