FeCoCrNiAlx高熵合金的电爆合金化

电爆喷涂是一种表面改性的新方法，它是利用高电压对喷涂材料脉冲放电，瞬时大电流将其加热并发生爆炸，产生高温粒子伴随冲击波喷射到基体表面形成涂层。本文提出了电爆法制备高熵合金涂层的新工艺，利用XRD、SEM、EDS以及电流电压波形对该方法制备高熵合金涂层的可行性进行了研究。结果表明，FeCoCrNiAlx (x=0, 0.5, 1.0)合金系涂层都形成了简单的FCC、BCC及FCC+BCC结构固溶体，并且随着Al含量的增加，该涂层的相结构由FCC相逐渐向BCC相转变。涂层表面平整、致密，没有明显的裂纹，且元素均匀分布在涂层表面，并没有发现明显的元素偏聚现象。初始充电电压11kV下的能量沉积为285.770 J，平均沉积效率达到48.8%。随Al含量的增加，涂层显微硬度逐渐增大，当x=1.0时平均显微硬度达到最大值531.8HV，大约是基体显微硬度的2倍。可以看出，电爆法实现了高熵合金涂层的成功制备。

Electric-explosive alloying of FeCoCrNiAlx high-entropy alloy

Electric-explosive spraying is a new method of surface modification. It uses high voltage to pulse discharge the sprayed material, and the instantaneous high current heats it and explodes, producing high-temperature particles that are sprayed onto the surface of the substrate along with the shock wave to form a coating. In this paper, a new process of preparing high entropy alloy coating by electric explosion method is proposed. The feasibility of this method to prepare high-entropy alloy coatings was studied by XRD, SEM, EDS, and current and voltage waveforms. The results show that FeCoCrNiAlx (x=0, 0.5, 1.0) alloy coatings have formed simple solid solutions of FCC, BCC and FCC+BCC structures, and the phase structure of the coating gradually changes from FCC phase to BCC phase with the increase of Al content. The surface of the coating is smooth and dense, without obvious cracks, and the elements are evenly distributed on the surface of the coating, and no obvious element segregation is found. The energy deposition under the initial charging voltage of 11kV is 285.770 J, and the average deposition efficiency reaches 48.8%. With the increase of Al content, the microhardness of the coating gradually increases. When x=1.0, the average microhardness reaches the maximum value of 531.8HV, which is about twice the microhardness of the substrate. It can be seen that the high entropy alloy coating is successfully prepared by electric-explosive method.