用高速电弧喷涂技术(HVAS)制备FeCrAl涂层,测试涂层在800℃的氧化性能,研究涂层在喷涂态和氧化后的组织结构。结果表明,由于冷却速率极快,FeCrAl涂层中形成比较多的Fe-Cr非晶态相,还有少量的Cr1.3Fe0.7O3和体心立方晶格的Fe-Cr固溶体,喷涂过程中Al的氧化比较严重。FeCrAl涂层的抗高温氧化性明显高于12Cr1MoV钢,接近于T91钢,涂层具有优异的抗氧化性一方面是由于层片间形成保护性的Cr氧化膜,阻止进一步氧化,也与含有较多抗氧化性好的非晶态相有关。高温氧化后,涂层中部分非晶态相晶化,转变为Fe-Cr晶体相。

FeCrAl coatings were prepared on low carbon steel substrate by high velocity arc spraying(HVAS)technology.The oxidation performance of coatings at elevated temperature was tested,microstructures of the sprayed and oxidized coatings were investigated.Results indicated that the as-sprayed coating was consisted of Fe-Cr amorphization mainly,together with crystallic phases such as Cr1.3-Fe0.7O3 and Fe-Cr solution crystals,which could be concluded that a very high cooling rate was obtained during HVAS process.The great mass of Al was oxidized during the spraying,which was existed in form of Al2O3.The oxidation resistances of coatings at elevated temeprature was much higher than that of 12Cr1MoV steel and approximately follows that of T91 steel.The excell oxidation resistances of FeCrAl coating was due to the chromium oxide pretective film would be formed at layers of the coating, moerever it was closely relation to the formation of Fe-Cr amorphization with high resistances to oxidizing.After being oxidatized at 800℃ for 260h,partial amorphization structures were crystallized and transformed into the fine Fe-Cr crystallic phase.