ウエダ　ヨシオ   Ueda Yoshio   上田　良夫    所属   追手門学院大学  理工学部 電気電子工学科    職種   教授
言語種別	英語
発行・発表の年月	2014/10/01
形態種別	論文
査読	査読あり
標題	Critical concentration for hydrogen bubble formation in metals
執筆形態	共著・編著（代表編著を除く）
掲載誌名	Journal of Physics Condensed Matter
掲載区分	国外
出版社・発行元	Institute of Physics Publishing
巻・号・頁	26(39)
国際共著	国際共著
著者・共著者	Lu Sun,Shuo Jin,Hong-Bo Zhou,Ying Zhang,Wenqing Zhang,Y. Ueda,H. T. Lee,Guang-Hong Lu
概要	Employing a thermodynamic model with previously calculated first-principle energetics as inputs, we determined the hydrogen (H) concentration at the interstitial and monovacancy as well as its dependence on temperature and pressure in tungsten and molybdenum. Based on this, we predicted the critical H concentration for H bubble formation at different temperatures. The critical concentration, defined as the value when the concentration of H at a certain mH-vacancy complex first became equal to that of H at the interstitial, was 24 ppm/7.3 GPa and 410 ppm/4.7 GPa at 600 K in tungsten and molybdenum in the case of a monovacancy. Beyond the critical H concentration, numerous H atoms accumulated in the monovacancy, leading to the formation and rapid growth of H-vacancy complexes, which was considered the preliminary stage of H bubble formation. We expect that the proposed approach will be generally used to determine the critical H concentration for H bubble formation in metals.
DOI	10.1088/0953-8984/26/39/395402
ISSN	1361-648X/1361-648X