Formation of Fine and Dense Conical Carbides on Tool Steel Surface by Sputter Etching

Abstract

Sputter etching of W-Cr-V tool steel specimens containing various amount of residual carbide was carried out by using an RF magnetron sputtering apparatus. For a fully solution-treated specimen having a very small amount of residual carbide, fine and sharp conical carbides with high density and homogeneity are formed on the surface by such treatment. With increasing sputter etching time, the carbides grow to a thick layer but lose their sharpness, part of the layer disappears and a particle-free matrix appears after long time etching. For the quenched and tempered specimen having a large amount of residual carbide, sharp carbides are newly formed among them but the tops of the residual carbides are not sharp. However, the carbide layer formed on the specimen remains even after a long sputter etching time.