Authors: Shinji Konosu Hidenori Shimazu Ryohei Fukuda
Publish Date: 2015/09/21
Volume: 46, Issue: 12, Pages: 5626-5637
Abstract
The tearing resistance dJ/da of conventional 225Cr1Mo steels and a Vbearing steel 225Cr1Mo03V steel with internal hydrogen was measured using the effective offset potential drop method Internal hydrogen refers to test specimens that are precharged thermally charged prior to testing In general CrMo steels used widely in the refining and petrochemical industries are susceptible to temper embrittlement However very few studies have dealt with the effects of hydrogen and temper embrittlement on the tearing resistance Test specimens were prepared by subjecting them to normalizing tempering and postweld heat treatments that simulated actual conditions Some specimens were embrittled by step cooling Hydrogen substantially reduced dJ/da for all samples except for that for the Vbearing steel and temper embrittlement caused additional adverse effects on dJ/da for samples with internal hydrogen for which the temper embrittlement parameter ie the Jfactor was large
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