Fast W/Ni alloying on medium carbon steel surface via scanning electron beam for excellent mechanical properties

Abstract

Next-generation medium carbide steel development requires fabricating novel structural materials with superior mechanical properties. Herein, scanning electron beam alloying is proposed for obtaining a W/Ni alloy coating on medium carbon steel, and the impact of process parameters on the microstructure and properties are investigated. Results demonstrated that the microstructure of alloying zone is martensite, α-Fe (Ni, C) solid solution, and W3C particles scattered along the grain boundaries. The transition zone between coating and substrate exhibits multiple sublayers: different morphological martensitic and heat-affected zone. As the energy density rises, the mechanical properties of the coating initially increase and subsequently decline. The microstructural findings revealed that the formation of α-Fe (Ni, C) solid solution, martensitic, and carbides play a critical role in substantially enhancing mechanical properties. This work produced a high-performance W-Ni composite coating on medium carbon steel.