钢表面粉末包埋渗铝的表面状态及元素扩散机理研究进展

Research Progress on Surface State and Element Diffusion Mechanism of Steel with Surface Coating Prepared by Pack Aluminizing Method

钢铁作为基础性结构材料,应用在国民经济的各个领域。由于钢材在工程应用中会发生氧化、腐蚀,采用粉末包埋渗铝对钢材进行表面改性可提高其抗氧化性能和腐蚀性能。目前为止,关于渗铝工艺参数对渗层微观组织、表面状态和元素扩散机理的研究,比较零散,缺乏系统总结。综述渗铝工艺参数对粉末包埋渗铝钢的微观组织、表面状态及其性能的影响,分析渗铝工艺参数与渗层微观组织的关联;概括渗铝工艺参数对Fe-Al元素扩散系数和扩散激活能的影响规律,分析Fe-Al元素扩散机制;总结渗铝层预测模型,对粉末包埋渗铝钢的研究趋势进行展望。

As fundamental structural materials,steels are widely applied in the national economical fields.Since the oxidation and corrosion occur at steels in engineering applications frequently,surface modification on steel through pack aluminizing can contribute to improve their oxidation resistance and corrosion performance.So far,the effect of aluminizing parameters on the microstructure of coatings,surface integrity and mechanisms for element diffusion is relatively dispersed,which is also deficient and need to be sum up systematically.Accordingly,the impact of aluminizing parameters on the microstructure,surface state and properties of pack aluminized steel was reviewed,and the relationship between aluminizing process parameters and microstructure of the layer was analyzed.In addition,the influence rules of aluminizing process parameters on diffusion coefficient and diffusion activation energy of Fe-Al element were summarized.Also,element diffusion mechanism of Fe-Al and the diffusion mechanism of Fe-Al element was analyzed.The prediction models of aluminized layer is summarized and the tendency of research for aluminized steel prepared via pack cementation has been forecasted.