金属镁的氧化及氧化机理研究进展

Research Progress on Oxidation and Oxidation Mechanism of Magnesium

镁合金作为目前最轻的商用金属结构材料,在航空航天、汽车、3C产品等领域具有广泛的应用前景。同时,面对全球铁铝资源日趋紧缺和我国大量进口铁铝矿石的困境,推广应用镁合金材料具有重要的战略意义。与常用的钢铁材料和铝合金相比,镁合金的研究与开发还不充分,应用也受限。镁合金的耐腐蚀性能差,部分原因是镁的化学活性高,且表面生成的保护膜不具备保护作用。尤其在高温下,镁及其合金极易氧化,甚至燃烧,释放大量的热,这成为限制镁合金大量推广应用的瓶颈之一。针对镁及其合金极易氧化的问题,近年来研究学者围绕其氧化机制和影响因素开展了大量的研究,认为镁合金的氧化受氧化膜P-B值、镁的蒸发、扩散等因素影响。目前,大多通过合金化的方式来提高镁的抗氧化性。镁合金抗氧化性研究为高抗氧化性镁合金的研发提供了理论支持,同时扩大了镁合金的高温应用前景,并将为镁合金行业带来巨大的经济效益。本文归纳总结了国内外镁及其合金氧化特征及氧化机理的研究进展。首先,简述了镁的氧化;然后,分析了镁氧化的机理和影响因素,重点讨论了P-B值、扩散、蒸发、金相组织、合金元素对镁及其合金氧化行为的影响规律及作用机理;最后,总结了目前研究中的不足,提出了镁抗氧化性研究方向的建议。

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.