激光熔覆Al_xCrFeCoCuNi高熵合金涂层的显微组织与性能研究

Microstructure and properties of laser cladding Al_xCrFeCoCuNi high entropy alloy on AISI 1045 steel substrate

采用CO2激光熔覆技术在AISI 1045钢基底上制备了Al_xCrFeCoCuNi涂层。通过改变Al的含量来研究其对显微组织和耐磨性能的影响。涂层的微观结构、化学成分和相结构分别通过扫描电镜、能谱和X射线衍射进行了分析。研究结果表明,Al_xCrFeCoCuNi高熵合金涂层主要包括熔覆层、结合区和热影响区。熔覆层和基底具有很好的冶金结合。熔覆层主要由等轴晶和柱状晶组成。XRD分析可知,由于高熵效应使得Al_xCrFeCoCuNi高熵合金涂层相结构主要为简单面心和体心立方结构。Al_xCrFeCoCuNi的表面硬度最高可以达到758Hv,是基底的3倍,而且显微硬度随着Al含量的增加而升高。Al含量高的涂层具有高的硬度,从而提高了耐磨性能。

The Alx CrFeCoCuNi high entropy alloys （HEA）were prepared by laser cladding.Al contents were adj usted for further investigating the effect on wear resistance of sample.The microstructure,chemical compo-sition and phase analyses of the cladding layer were studied by scanning electron microscopy,EDS analysis,and X-ray diffraction measurement.The result shows that,Alx CrFeCoCuNi HEA samples consist of the cladding zone,bounding zone and heat affected zone.The bounding between cladding layer and the substrate of a good combination;the cladding zone is composed mainly of axis crystal and columnar crystals.The Alx CrFeCoCuNi HEA coating phase structure simple （FCC and BCC structure）due to high-entropy effect.The surface micro-hardness of AlxCrFeCoCuNi HEA samples up to 758 Hv,about 3 times as the substrate,and the hardness in-creases with increasing Al content.The high Al content gives a large improvement in wear resistance due to its high hardness.So the coating can play a good protective role on substrate AISI 1045 steel.