Influence of Medium Used during Ferritic Nitro-Carburizing of AISI H-13 Hot Work Tool Steel

Abstract

Ferritic nitro-carburizing is one of the most popular surface hardening methods used to improve lifespan of hot work tool steels. Different types of mediums like gas, liquid, plasma and fluidized bed are generally used during ferritic nitro-carburizing process. In this paper, various ferritic nitro-carburizing methods were compared where gas, salt bath and fluidized are used as mediums. AISI H-13 hot work tool steel specimens were treated by using these different methods of nitro-carburizing and their performance was evaluated by using micro-structural and mechanical analysis. Optical microscopy, micro-hardness testing and X-ray stress analyzer were used for specimen characterization. Moreover, pin on disk dry sliding wear tests were performed to compare wear performance of specimens treated with different nitro-carburizing methods. It is perceived that, medium used during nitro-carburizing has significant influence on the final surface properties that can be achieved by ferritic nitro-carburizing.