【摘要】：由于經濟的發(fā)展,對鋼材的磨損和高溫損耗越來越嚴重,所以對于鋼材的高溫氧化性及耐磨性具有一定的要求。目前,對于鋼材的保護最常用的就是表面處理,而熱噴涂制備涂層是表面處理中最常用的方法。電弧噴涂是熱噴涂最優(yōu)秀的方法之一,它具有低成本,高效率,操作簡單,方便等優(yōu)點。鋁涂層具有獨特的高溫抗氧化性,而且Fe-Al金屬間化合物具有硬度和抗高溫氧化,耐磨性,廣泛應用于抗高溫材料和耐磨性材料中,所以利用Al涂層制備Fe-Al金屬間化合物能滿足鋼材表面的抗損耗的要求,能大大提高了材料的使用壽命。在低碳鋼中Al的擴散厚度決定了Al涂層對基體材料保護能力的大小以及涂層的工作壽命。擴散厚度越深,則涂層的保護能力越強,使用壽命越長。所以研究形成擴散層的工藝和擴散系數是十分必要。本文采用電弧噴涂制備Al涂層,再利用加熱擴散方法形成Fe-Al金屬間化合物,研究經過加熱處理后的Al涂層和擴散層形貌,顯微組織,相的組成,并測試了Al涂層高溫抗氧化性及硬度,擴散層的顯微硬度。結果表明:涂層厚度、加熱時間和加熱溫度能促進擴散層的形成,1000℃的Fe-Al相擴散系數為2.5×10-11m2s-1,涂層及擴散層的硬度得到顯著提高。本文采用電弧噴涂制備Fe-Al雙絲涂層的,再經過加熱處理得到鐵鋁間金屬間化合物涂層,觀察了涂層的形貌及相的組成,并測試復合涂層的抗高溫氧化性,及其顯微硬度。實驗結果表明:Fe-Al雙絲涂層經過加熱擴散之后沒有形成擴散層,涂層加熱800℃時主要形成Fe Al,Fe Al_2,Fe_2Al_5,涂層加熱900℃時主要形成Fe Al_2,Fe Al_3,Fe_2Al_5。經過熱處理雙絲涂層硬度比Al涂層硬度提高4-5倍,經過熱處理的雙絲涂層的抗高溫氧化性能比較優(yōu)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，

本文編號：2454280