CoCrFeNi基高熵合金熔体在碳化钨表面的润湿性能

Wettability of CoCrFeNi-based high entropy alloy melt on tungsten carbide surface

为合理选择高熵合金黏结相,采用真空电弧熔炼法制备了CoCrFeNi、CoCrFeNiAl、CoCrFeNiAlTi等3种CoCrFeNi基高熵合金,用座滴法研究3种高熵合金熔体在碳化钨(WC)表面的润湿性能,并对润湿试样特征区域的成分和形貌进行表征。结果表明:CoCrFeNi基高熵合金熔体在WC表面的润湿过程分为迅速铺展和缓慢铺展2个阶段,活性元素在WC表面吸附扩散后形成前驱膜;CoCrFeNi基高熵合金熔体在WC表面的润湿为反应润湿类型,其中CoCrFeNi/WC体系中WC的溶解对润湿起重要作用,而CoCrFeNiAl/WC和CoCrFeNiAlTi/WC体系的润湿主要取决于界面反应;CoCrFeNi、CoCrFeNiAl、CoCrFeNiAlTi等3种高熵合金在WC表面有良好的润湿性能,平衡接触角分别为4.10°、7.03°和3.62°。

In order to select the high-entropy alloy binder phase reasonably, three kinds of CoCrFeNi-based high-entropy alloys, including of CoCrFeNi, CoCrFeNiAl and CoCrFeNiAlTi, were prepared by the vacuum arc melting method, and the wetting of the three kinds of high-entropy alloy melts on the surface of tungsten carbide(WC) was studied by the sessile drop method. The composition and morphology of the characteristic areas of the wetted samples were characterized. The results show that the wetting process of the CoCrFeNi-based high-entropy alloy melt on the WC surface can be divided into two stages: rapid spreading and slow spreading. The active elements are adsorbed and diffused on the WC surface to form a precursor film. The wetting of the CoCrFeNi-based high-entropy alloy melt on the WC surface is a reactive wetting type, in which the dissolution of WC in CoCrFeNi/WC system plays an important role, while the wetting of the CoCrFeNiAl/WC and CoCrFeNiAlTi/WC systems mainly depends on the interface reaction. CoCrFeNi, CoCrFeNiAl and CoCrFeNiAlTi high-entropy alloys have good wettability on WC surface, and the equilibrium contact angles are 4.10°, 7.03° and 3.62°, respectively.