In-situ CrFeCoNi medium entropy alloying coating via electrospark powder deposition

Medium or high-entropy alloys have led to widespread interest in their preparation, property control, and applications. The ability to apply these new alloys as coatings on conventional materials allows alternative surface treatment methods. This study used electrospark deposition with powder feedstock, to form MEA coating with fine-tuned compositions on steel substrate. Single-phase CrFeCoNi MEA using optimized ESD parameters and powder formulation. The phase and composition of MEA coatings and their hardness were also characterized. The coating showed two orders of magnitude reduction in specific wear rate coefficient compared with that of bare A516 steel substrate. This study demonstrates that the powder-based ESD technique can be used to create in-situ M/HEA coatings for applications requiring improved properties.