Application of Coating Technique for Measurement of Elevated Temperature Fatigue Crack Growth Behavior

J. Ocean Eng. Technol. 2002;16(2):60-66.

고온 피로균열 성장거동 관찰을 위한 코팅기술의 응용

남승훈,김용일,서창민,김동석

한국표준과학연구원 산업측정표준부,한국표준과학연구원 물질량표준부,경북대학교 기계공학부,삼익정공(주) 기술연구소

Keywords: Coating Technology, Elevated Temperature Fatigue, Crack Growth, Remote Measurement System

핵심용어: 코팅기술, 고온 피로, 균열성장, 원거리측정시스템

Abstract

The remote measurement system(RMS) as a new experimental method is limited in its application to crack measurement at elevated temperatures because of the oxide layer on the specimen surface. Since TiAIN and Cr coating layers have a high resistance to oxidation and wear, this paper proposed a TiAIN and Cr coating technique for specimens to facilitate the measurement of crack growth behavior using RMS. To investigate the effects of the coating layer, tension and fatigue tests were carried out at room temperature and at $538^{circ}C$. The test material was 1Cr-1Mo-0.25V steel which is widely used as a turbine rotor material. From the experimental results, it was found that the mechanical properties of the TiAIN and Cr coated specimens were similar to those of the substrate. Accordingly, the TiAIN and Cr coated layer had hardly any influence on the fatigue crack propagation.