Fatigue Strength Characteristics of 1Cr-1Mo-0.25V Steel by Improved TiN Coated Processes

J. Ocean Eng. Technol. 1997;11(4):49-60.

TiN코팅 공정 개선에 의한 1Cr-1Mo-0.25V 강재의 피로강도 특성

서창민,김경렬

경북대학교 기계공학부,포항공과대 가속기연구소

Keywords: Arc Ion Plating, Droplet, TiN Coated Steel, Fatigue Strength

핵심용어: 아크 이온 플레이팅, 드롭렛, TiN 코팅강, 피로강도

Abstract

This paper deals with the effect of coating layer on the fatigue strength of TiN coated 1Cr-1Mo-0.25V steel prepared by using the arc ion plating (AIP) process, in which it was characterized by the presence of extractor grid (ion filter). The rotary bending fatigue tests were carried out under room air conditions, and the fatigue crack initiation and growth bwhavior were observed by using plastic replica method. As experimental results, it was found that the obvious improvement of fatigue life at lower stress region was confirmed in TiN coated specimen processed with ion filter. It was also exlained that the increase of fatigue life in the case of an improved AIP process with ion filter was attributed to the retardation of crack initiation of the substrate surface due to hard coating layer, more densly formed with the reduced size and density of droplets.