Protection method of magnesium alloy workpiece for marine environment

Abstract

The invention discloses a protection method of a magnesium alloy workpiece for a marine environment, which adopts double-layer protection of an inner layer and an outer layer, and comprises the steps of micro-arc oxidation, conductive paint coating, baking and curing, alkaline chemical nickel plating, acidic chemical nickel plating, sealing and drying, the inner layer adopts a micro-arc oxidation film which is firmly combined with a matrix, and the outer layer adopts a micro-arc oxidation film which is firmly combined with the matrix; the outer layer adopts double-layer nickel plating of a bottom plating layer and a surface plating layer, the bottom plating layer adopts alkaline chemical nickel plating and is plated on the inner layer, the combination is firm, the surface plating layer adopts acid chemical nickel plating and is plated on the bottom plating layer, sealing treatment is performed, the porosity is reduced, the surface is compact, and the finished product is silver gray in appearance, slightly yellow, high in percent of pass, good in quality consistency and free of bubbling or layering phenomenon; through a 200 DEG C thermal shock test, the magnesium alloy micro-arc oxidation film is continuous, uniform, complete and free of pulverization, looseness and scratches, through a 672 h neutral salt spray test, the protection grade Rp is not lower than 9 grade, and the technical bottleneck that the magnesium alloy micro-arc oxidation film is difficult to be plated with a metal coating is broken through.

Description

Technical field [0001] The present invention belongs to the field of surface treatment technology, specifically relates to a marine environmental protection technology. Background [0002] Magnesium alloy is one of the lightest metal structural materials, low density than aluminum alloy, high strength and stiffness, low elastic modulus, superior damping and shock absorption performance, good thermal conductivity, machining performance and electromagnetic shielding performance, widely used in the automotive industry, aerospace and 3C product industry. [0003] Multifunctional measuring vessels are equipped with a variety of electronic equipment, which has strict weight restrictions, and the need for miniaturization and lightweighting is becoming more and more urgent. Magnesium alloys gradually replace aluminum alloys, such as TR components with a large installed number, which ensures the weight reduction effect and improves the maneuverability of the measuring ship. [0004] Magne...

AI Technical Summary

Problems solved by technology

This kind of magnesium alloy parts used in the harshest marine environment, a single conductive layer or a non-conductive covering layer, cannot meet the requirements of use, and has become a bottleneck restricting its application in specific fields