Evaluating the effects of number of stages in gas nitriding on nitrided layer of skd61 steel used for the aluminum extrusion die

Abstract

This study conducted experiments with one-stage and two-stages gas nitriding for SKD61 steel commonly used for the aluminum extrusion die. The results indicated that, although one-stage process for a longer time that created a deeper nitrided layer compared with two-stages process. The dimension variation of the specimen in each process was also proportional to the coating layer depth. However, the micro hardness of one-stage process coating layer was smaller. On the other hand, the cost of one-stage process was also more expensive. The research results contribute to build appropriate plans for specific purpose in design, fabrication and recovering dimension of aluminum extrusion die.