CTOD fracture toughness assessment method of High-strength steel based on BS7910

摘要

As one of the essential criteria of assessment to welding toughness, CTOD(Crack tip opening displacement) is widely applied in engineering. The research on allowable values of the CTOD of high strength and thickness steel has been a hot issue, therefore the theoretical research in China lags behind its overseas. The present paper takes the single edge fatigue precrack of CTOD specimen as a flaw with the technical route of the British Standard 7910-2005, that is "Guide to methods for assessing the acceptability of flaws in metallic structures". In the meanwhile, make the grading assessments of the welding seam center of the EQ70/56 joints, combining the results of the CTOD tests. The assessments on welded joints of EQ70/56 show that the CTOD values are in the acceptable range. This method provides some useful guidance in researches of allowable CTOD values.