Researchers found that atmospheric plasma-sprayed AlCoCrFeNi High Entropy Alloy (HEA) on SS316l can improve the corrosion resistance of stainless steel by forming a protective oxide layer using suitable annealing processes.

Research proves that coating stainless steel with AlCoCrFeNi High Entropy Alloy (HEA) using atmospheric plasma spraying and subsequent annealing at 550 °C is an effective method of improving corrosion resistance. Source: Adobe.Stock

The ability to endure extreme corrosion in challenging environments is reduced in stainless steel. This can be addressed by appropriate surface modification techniques to redefine the surface with the required properties. The characteristics of the atmospheric plasma sprayed AlCoCrFeNi High Entropy Alloy (HEA) on SS316l were presented in a current study. The coating characterisation revealed uniform coating with homogeneous deposition of gas-atomized AlCoCrFeNi HEA spanning for 150 μm. The coated substrates were further annealed for 2 h at 400 °C, 550 °C, 700 °C and 850 °C and the annealing at 550 °C offered enhanced microstructure. Annealing the coated sample at 550 °C offered a 46% improvement in microhardness against the uncoated sample post-annealing.