Designing AlCoCrFeNiTi high-entropy alloy with the directional array TiN by magnetic field-assisted laser cladding

The directional array TiN-reinforced AlCoCrFeNiTi high-entropy alloy (HEA) coatings were successfully synthesized by magnetic field-assisted laser cladding on Ti-6Al-4V (TC4) alloy. The effect of magnetic induction intensity of AlCoCrFeNiTi HEA coatings was investigated methodically on thermodynamic calculation, microstructure characterization and corrosion resistance. The results show HEA coatings are mainly composed of body-centered cubic (BCC) solid solution phase, (Ni, Co)Ti2 intermetallic compound and TiN ceramic phase. With 1 T magnetic induction intensity assisted laser cladding, the microstructures of in situ TiN display a "cross" shape of the directional array. In 3.5 wt.% NaCl solution, the 1 T HEA coating could significantly decrease the corrosion rate compared with TC4 alloy.