Material for surface composite modification of magnesium alloy made by lost foam casting (LFC) and preparation method thereof

Abstract

The invention discloses a material for surface composite modification of magnesium alloy. The material comprises the following compositions in percentage by mass: 30 to 50 percent of glass dust (with the melting point between 350 and 500 DEG C), 10 to 15 percent of metal powder, 0.4 to 0.6 percent of defoaming agent, 2.0 to 4.0 percent of caking agent, and the balance of water, wherein the glass dust is one of borate glass, phosphate glass and lead-zinc glass; the metal powder is at least one of aluminum powder and zinc powder; the defoaming agent is one of polydimethylsiloxane, polyoxyethylene polyoxypropylene ether and polyoxypropylene glycerol ether; and the caking agent is one of polyvinyl alcohol and sodium carboxymethyl cellulose. The prepared material is coated on a foamy surface to form an alloying layer and a ceramic layer synchronously during magnesium alloy casting; moreover, the compositions of the surface layer of a cast product is in ladderlike distribution from the outside to the inside to form a composite layer, thereby providing double protection for a matrix and increasing the corrosion resistance and abrasion resistance of the magnesium alloy. The material has the advantages of low cost, simple operation, easily controlled parameters, and the like.

Description

technical field [0001] The invention belongs to the technical field of metal surface modification to improve corrosion resistance, wear resistance, etc., and relates to a material and a preparation method for forming an alloyed / ceramic composite layer on the surface of a magnesium alloy through a lost foam casting process. The invention has the advantages of low cost, simple process, easy operation and the like. Background technique [0002] Lost foam casting is an economical and effective green casting process for producing high-quality near-net-shape and complex castings. It is currently the fastest-growing new casting process. In Europe and North America, lost foam casting has become a popular choice for the production of aluminum alloy cylinder blocks and cylinder heads for automobiles. The main forming process of products such as gearbox housings and intake manifolds. In recent years, a lot of research has been done on the lost foam casting technology of magnesium allo...

AI Technical Summary

Problems solved by technology

The anodic oxidation and micro-arc oxidation layers are relatively thin, and the anti-corrosion effect is poor. Laser treatment is not suitable for complex castings, and the cost of ion implantation is high. Therefore, traditional treatment methods have certain limitations for lost foam casting magnesium alloy castings.