铝含量对Al_xCrFeCoCuNi高熵合金涂层抗氧化性能的影响

Effect of Aluminum Content on Oxidation Resistance of Al_xCrFeCoCuNi High Entropy Alloy Coating

采用激光熔覆技术在45#钢基底上制备了Al_xCrFeCoCuNi(x=0.5、2.0、4.0)高熵合金涂层,研究了Al含量x对涂层的抗氧化性能的影响规律。利用扫描电镜、能谱仪和X射线衍射仪对涂层结构进了测定,进而揭示铝含量的影响。结果表明,高熵合金涂层主要由简单面心和体心立方结构的固溶体组成,并且随着铝含量增加到x=4时完全转变为单一的体心立方结构。在900℃大气气氛中氧化动力学曲线表明Al_xCrFeCoCuNi高熵合金涂层具有较好的抗氧化性能,并且随着Al含量的增加而提高。这是因为高温氧化后其表面主要生成了Al_2O_3和Cr_2O_3保护膜,从而提高了Al_xCrFeCoCuNi高熵合金涂层的抗氧化性能。

Al_xCrFeCoCuNi（x=0.5、2.0、4.0）high entropy alloy coatings were prepared on 45 steel surface by laser cladding technology,and the effect of the aluminum content xon the oxidation resistance of the coating were studied.The cross-sectional microstructure of the coating were analyzed by SEM,XRD and EDS.The results show that,the as-clad coating is composed of FCC and body center cubic BCC solid solution.The oxidation tests show that the addition of Al effectively improves the oxidation resistance of Al_xCrFeCoCuNi at 900 ℃ in air.The formation of a dense and adherent scale consisting of Cr_2O_3 and Al_2O_3 is supposed to be responsible for the observed improvement of the oxidation resistance.