The Study of Infrared Thermography of a Mild Steel for Nondestructive Evaluation

J. Ocean Eng. Technol. 2008;22(2):72-77.

Han Jeong-Seb,Park Jin-Hwan

Dept. of Materials Science and Engineering DongA Univ.,Devision of Chemical Engineering PuKyung Univ.

적외선 카메라에 의한 연강의 비파괴 평가에 대한 연구

한정섭,박진환

동아대학교 신소재공학과,부경대학교 응용화학공학부

Keywords: Infrared thermograph, Defect size, Non-destructive testing, The full with at half of the maximum contrast, Mild steel

핵심용어: 적외선 열화상, 결함의 크기, 비파괴시험, 반치폭, 연강

Abstract

The application of infrared thermography for detecting defects under the surface of a material was studied. Defects in a specimen were made by back-drilled circular holes. To get alarge temperature difference at the surface, a halogen lamp was used for surface heating. We confirmed that the defect location had a good relationship with the maximum temperature difference. The sizes of the defects could be calculated by means of the FWHM. The value of the FWHM of a temperature difference decreased with time. Therefore in an extremely short time after the heating, the true defect size could be measured.