Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : October 07, 2017 - October 09, 2017
The hydrogen atom interacts various lattice defects and secondary particles in a material, causing a degradation in the tensile strength and elongation, well-known as hydrogen embrittlement (HE). Such material-hydrogen interaction should be extensively investigated to elucidate a precise mechanism of the HE. This study investigated hydrogen-entry properties and hydrogen state of an aluminum alloy 6061-T6 exposed to high-pressure hydrogen gas by means of thermal desorption analysis (TDA) and secondary ion mass spectrometry (SIMS). The TDA revealed that the hydrogen entry in the alloy occurred under the present hydrogen-exposure condition and the hydrogen was trapped by an extremely-deep trapping site, compared to ordinary trapping sites (lattice, dislocation, and vacancy) previously reported. To detect reliable signals of hydrogen trapped in the alloy by SIMS, removal of background-originated hydrogen derived from water or hydrocarbon molecules and verification of false signals produced due to a difference in sputtering rate between the phases were thoroughly conducted. Consequently, it was revealed the hydrogen was trapped by micrometer-sized intermetallic particles.
