热喷涂铝—铁涂层反应改性机理及工艺研究
发布时间：2019-04-07 17:43
【摘要】：由于经济的发展,对钢材的磨损和高温损耗越来越严重,所以对于钢材的高温氧化性及耐磨性具有一定的要求。目前,对于钢材的保护最常用的就是表面处理,而热喷涂制备涂层是表面处理中最常用的方法。电弧喷涂是热喷涂最优秀的方法之一,它具有低成本,高效率,操作简单,方便等优点。铝涂层具有独特的高温抗氧化性,而且Fe-Al金属间化合物具有硬度和抗高温氧化,耐磨性,广泛应用于抗高温材料和耐磨性材料中,所以利用Al涂层制备Fe-Al金属间化合物能满足钢材表面的抗损耗的要求,能大大提高了材料的使用寿命。在低碳钢中Al的扩散厚度决定了Al涂层对基体材料保护能力的大小以及涂层的工作寿命。扩散厚度越深,则涂层的保护能力越强,使用寿命越长。所以研究形成扩散层的工艺和扩散系数是十分必要。本文采用电弧喷涂制备Al涂层,再利用加热扩散方法形成Fe-Al金属间化合物,研究经过加热处理后的Al涂层和扩散层形貌,显微组织,相的组成,并测试了Al涂层高温抗氧化性及硬度,扩散层的显微硬度。结果表明:涂层厚度、加热时间和加热温度能促进扩散层的形成,1000℃的Fe-Al相扩散系数为2.5×10-11m2s-1,涂层及扩散层的硬度得到显著提高。本文采用电弧喷涂制备Fe-Al双丝涂层的,再经过加热处理得到铁铝间金属间化合物涂层,观察了涂层的形貌及相的组成,并测试复合涂层的抗高温氧化性,及其显微硬度。实验结果表明:Fe-Al双丝涂层经过加热扩散之后没有形成扩散层,涂层加热800℃时主要形成Fe Al,Fe Al_2,Fe_2Al_5,涂层加热900℃时主要形成Fe Al_2,Fe Al_3,Fe_2Al_5。经过热处理双丝涂层硬度比Al涂层硬度提高4-5倍,经过热处理的双丝涂层的抗高温氧化性能比较优秀。
[Abstract]:Due to the development of economy, the wear and wear of steel become more and more serious, so it has certain requirements for oxidation and wear resistance of steel at high temperature. At present, the most commonly used protection of steel is surface treatment, and thermal spraying coating is the most commonly used method in surface treatment. Arc spraying is one of the best thermal spraying methods. It has the advantages of low cost, high efficiency, simple operation and convenience. Aluminum coatings have unique high-temperature oxidation resistance, and Fe-Al intermetallic compounds have hardness and high-temperature oxidation resistance, wear resistance, and are widely used in high-temperature and wear-resistant materials. Therefore, the preparation of Fe-Al intermetallic compounds by Al coating can meet the requirements of anti-loss on the steel surface, and can greatly improve the service life of the materials. The diffusion thickness of Al in low carbon steel determines the protective ability of Al coating to the substrate and the working life of the coating. The deeper the diffusion thickness is, the stronger the protective ability of the coating is and the longer the service life of the coating is. Therefore, it is necessary to study the process of forming diffusion layer and diffusion coefficient. In this paper, Al coating was prepared by arc spraying, and then Fe-Al intermetallic compound was formed by heating diffusion method. The morphology, microstructure and phase composition of Al coating and diffusion layer after heating treatment were studied. The oxidation resistance and hardness of Al coating at high temperature and the microhardness of diffusion layer were also tested. The results show that the coating thickness, heating time and temperature can promote the formation of diffusion layer. The diffusion coefficient of Fe-Al phase at 1000 鈩，
本文编号：2454280
[Abstract]:Due to the development of economy, the wear and wear of steel become more and more serious, so it has certain requirements for oxidation and wear resistance of steel at high temperature. At present, the most commonly used protection of steel is surface treatment, and thermal spraying coating is the most commonly used method in surface treatment. Arc spraying is one of the best thermal spraying methods. It has the advantages of low cost, high efficiency, simple operation and convenience. Aluminum coatings have unique high-temperature oxidation resistance, and Fe-Al intermetallic compounds have hardness and high-temperature oxidation resistance, wear resistance, and are widely used in high-temperature and wear-resistant materials. Therefore, the preparation of Fe-Al intermetallic compounds by Al coating can meet the requirements of anti-loss on the steel surface, and can greatly improve the service life of the materials. The diffusion thickness of Al in low carbon steel determines the protective ability of Al coating to the substrate and the working life of the coating. The deeper the diffusion thickness is, the stronger the protective ability of the coating is and the longer the service life of the coating is. Therefore, it is necessary to study the process of forming diffusion layer and diffusion coefficient. In this paper, Al coating was prepared by arc spraying, and then Fe-Al intermetallic compound was formed by heating diffusion method. The morphology, microstructure and phase composition of Al coating and diffusion layer after heating treatment were studied. The oxidation resistance and hardness of Al coating at high temperature and the microhardness of diffusion layer were also tested. The results show that the coating thickness, heating time and temperature can promote the formation of diffusion layer. The diffusion coefficient of Fe-Al phase at 1000 鈩，
本文编号：2454280
本文链接：https://www.wllwen.com/kejilunwen/jiagonggongyi/2454280.html
