Anti-cavitation corrosion of laser-cladded CoCrFeNiAlx on TC4 surface

The influence of aluminum contents on the cavitation corrosion resistance of CoCrFeNiAlx high-entropy alloy (HEA) coatings deposited on TC4 via laser cladding was investigated in both distilled water and artificially simulated seawater. The results showed that the cavitation corrosion resistance of the coatings increased and then decreased with increasing Al content in both media. The weight loss rate was significantly higher in simulated seawater than in distilled water. Increasing the Al content led to a transition in the coating phase from a single FCC phase to FCC + BCC dual phases, which improved the corrosion resistance. However, as the BCC phase content increased, the plasticity of the coating decreased while the strength increased, reducing the coating’s ability to absorb cavitation energy and leading to severe cavitation damage.