Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (38권2호 79-82)

Adhesion Improvements of $TiB_2$ Coatings on Nitrided AlSl H13 Steel

$TiB_2$ 코팅의 접착력 향상을 위한 AlSl H13 steel의 질화처리

박보환;정동하;김훈;이정중;
Park Bohwan;Jung Dong-Ha;Kim Hoon;Lee Jung-Joong;

서울대학교 재료공학부;
School of Mater. Sci. Eng., Seoul National University;

Abstract

This study investigated the effect of nitriding on the hardness and adhesion properties of $TiB_2$ coatings. Inductively coupled plasma (ICP) was used for both nitriding and deposition. By applying ICP, H13 steel was nitrided at a high rate of $50;{mu}m/hr$. After nitriding, a Fe4N compound layer or a diffusion layer was formed according to the hydrogen/nitrogen ratio. Both layers could improve the load-bearing capacity of the substrate by increasing the substrate hardness. The adhesion of the $TiB_2$ coatings increased to $~30N$ after nitriding, but the hardness of the coating was lowered to 20-30 GPa. However, the adhesion of the $TiB_2$ coatings with a high hardness (>60 GPa) could not be improved substantially by nitriding due to the large difference in hardness between the coating and the substrate. The grain size of the $TiB_2$ coating was larger on the nitrided substrates, resulting in a decrease in the hardness of the coating.

Keywords

Inductively coupled plasma[ICP];Plasma nitriding;