[T19] High Entropy Alloys

[14D-T19-07] Promising Hot Corrosion Resistance of Coating Synthesized by Extreme High-Speed Laser Cladding AlCoCrFeNi_2.1 High-Entropy Alloy Powder

*B. Yang¹, L. Zhang¹ (1.University of Science and Technology Beijing, China)

Keywords:Extreme high-speed laser cladding, High entropy alloy, Coating, Hot corrosion

High entropy alloys (HEAs) have received extensive attention during the two decades. Their excellent performance makes them broad prospects for application. However, the current market saturation of HEAs is low. Here, extreme high-speed laser cladding and multiple laser remelting are used to improve hot corrosion resistance of AlCoCrFeNi_2.1 high-entropy alloy coating by introducing high densities of dislocations and higher compressive residual stresses (CRSs). The dislocations promote the diffusion of Al to form Al-rich oxide layer. The higher CRSs suppress the initiation and propagation of cracks as well as enhance the adhesion between the oxide layer and the substrate. They improve significantly the hot corrosion resistance of the coating immersed in a molten salt of 75% Na₂SO₄ + 25% NaCl at 900°C. These observations provide an effective approach for designing elevated-temperature materials.