SKD61과 Radical Nitriding 처리된 SKD61 기판상에 Arc Ion Plating으로 증착된 TiN 박막의 미세구조 및 기계적 특성, 마찰 및 접착력에 관한 연구

• Published in: Biuletyn Uniejowski Vol. 40; no. 6; pp. 254 - 257
• Main Authors: 주윤곤(Yun-Kon Joo), 윤재홍(Jae-Hong Yoon), 방위(Wei Fang), 장세굉(Shi-Hong Zhang), 조동율(Tong-Yul Cho), 하성식(Sung-Sik Ha)
• Format: Journal Article
• Language: Korean
• Published: 한국표면공학회 2007
• Subjects: 기계공학; Bind coating; Arc ion plating; Adhesion; Radical nitriding; TiN film
• ISSN: 1225-8024; 2299-8403; 2288-8403

TiN coating on tool steel has been widely used for the improvement of durability of tools. In this work, radical nitriding(RN) is carried out on SKD61 at $450^{\circ}C$ for 5 hours in the ammonia gas pressure $2.7{\times}10^3\;Pa$. The TiN coating is carried out by arc ion plating(AIP) with the process parameters: arc power 150 A, bias voltage -50V, coating time 40 minutes and nitrogen gas pressure $4{\times}10^3\;Pa$. Hardness, elastic modulus, friction coefficient and adhesion of TiN coating on substrates of both TiN/SKD61 and TiN/RN SKD61 coatings are investigated comparatively. The primary crystalline faces of TiN surface are(200) and(111) for TiN/SKD61 and TiN/RN SKD61 respectively. In addition to the primary phase, Fe phase exists in TiN/SKD61 coating, but not in TIN/RN SKD61. The hardness of TiN/RN SKD61 is about 700 Hv, 250 Hv(56%) higher than that of TiN/SKD61 at the near interface of TiN and substrates. At the TiN surface, hardness of TiN/RN SKD61 is 2,149 Hv, 71 Hv(3%) higher than that of TiN/SKD61. The elastic modulus of TiN coating is improved to 26.7 GPa(6%) by radical nitriding. The adhesion is improved by the RN coating showing no spalling. buckling and chipping on the scratch test track which are shown on the non-RN TiN/SKD61.