金属镁的氧化及氧化机理研究进展

As the lightest commercial metal structure material, magnesium alloy shows a wide application prospect in aerospace, automobile, 3C pro-ducts and other fields. At the same time, it is of great strategic significance to promote the application of magnesium alloy materials, in the face of the increasing shortage of iron and aluminum resources in the world and the dilemma of a large number of imported iron and aluminum ores. Compared with common steel and aluminum alloy, the research and development of magnesium alloy are not enough, and its application is also limited. The poor corrosion resistance of magnesium alloy is partly due to the high chemical activity of magnesium and the lack of protective effect of the film formed on the surface. Especially at high temperature, magnesium and its alloys are easy to oxidize, even burn, and release a lot of heat, which has become one of the bottlenecks limiting the extensive application of magnesium alloys. In recent years, a lot of researches have been carried out on the oxidation mechanism and influencing factors of magnesium and its alloys. It is considered that the oxidation of magnesium alloy is affected by factors, such as P-B value of oxide film, evaporation and diffusion of magnesium and so on. At present, the oxidation resistance of magnesium is improved by alloying. This provides theoretical support for the preparation of magnesium alloy with high oxidation resistance. At the same time, it expands the application prospect of magnesium alloy at high temperature, and will bring huge economic benefits to magnesium alloy industry. This paper summarizes the research progress of oxidation characteristics and mechanism of magnesium and its alloys at home and abroad. Firstly, the oxidation of magnesium is briefly introduced. Secondly, the mechanism and influencing factors of magnesium oxidation are analyzed, and the influence rules and mechanism of P-B value, diffusion, evaporation, microstructure and alloy elements on the oxidation behavior of magnesium are emphatically discussed. Finally, the shortcomings of the current research are summarized, and suggestions on the research direction of magnesium oxidation resistance are put forward.