Microstructure and high-temperature oxidation resistance of in-situ Al2O3 reinforced AlCrFeTiV high-entropy alloy with boron microalloying
Yaxia Liu, Hongxi Liu, Hongxi Liu, Chen Yang, Yueyi Wang, Xuanhong Hao, Haifang Liu, Haifang Liu, Xiaowei Zhang
Abstract
In this study, the effect of boron (B) on the microstructure and high-temperature oxidation resistance of AlCrFeTiV high-entropy alloy (HEA) coatings were investigated via laser cladding on Ti-6Al-4 V. The study findings indicate that AlCrFeTiVBx (x=0, 0.5, and 1 at%) HEAs coatings mostly comprise BCC solid solution phase, TiO 2 and Al 2 O 3 ceramic particles, which formed by oxygen (O) in the air reacts with Titanium (Ti) and Aluminum (Al) of coatings. Besides, the introduction of minor B should effectively reduce the formation of TiO 2 . Increasing the B content, significantly promoted the high-temperature oxidation resistance of HEAs coatings at 900 °C for 50 h. When x = 1, the coating exhibits the best high-temperature oxidation resistance . Furthermore, the oxidation mechanism of the coating was studied using first-principles calculations, and further investigation was utilized on the charge transfer of oxygen adsorbed on the BCC (1 0 0) surface.