Interfacial Microstructure of FeCoNiCrAl0.1 High Entropy Alloy and Pure Copper Prepared by Explosive Welding
Qichao Tian, Hanliang Liang, Yang Zhao, Honghao Ma, Zhaowu Shen, Yuling Sun, Ming Yang
Abstract
The FeCoNiCrAl0.1 high entropy alloys (HEAs) and pure copper (Cu) composite plates were successfully fabricated by the explosive welding technique using two different gap distances. The interfacial microstructure, elemental distribution, grain structure of vortex zone and hardness were characterized using optical microscopy (OM), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD), nanoindentation and micro-hardness tester. The explosive weldability window was calculated to verify the weldability of HEAs and Cu. The results indicated that the Cu/HEA composites presented typical wavy structures without visible defects and have an excellent bonding quality. The elements mixed and formed intermetallic compounds at the vortex zones. The grains near the vortex zones showed strong deformation, and phase transformation occurred. Compared with the matrix metals, the hardness of Cu and HEAs increased near the welding interface and sharply increased to 375 HV near the vortex zone.