Journal of Shanghai University(Natural Science Edition) ›› 2011, Vol. 17 ›› Issue (4): 487-502.doi: 10.3969/j.issn.1007-2861.2011.04.016
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CHEN Ye-xin
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Abstract: The research of two kinds of environmental hydrogen embrittlements in intermetallic at room temperature is summarized in this paper. Environmental embrittlement of intermetallic involves two main processes: generation of atomic hydrogen and diffusion of hydrogen in the alloy. The experimental results have verified that the ways of hydrogen atom generation are surface reaction of active elements with water vapor in air and catalysis reaction of molecular H2 induced by transition metal atoms in gaseous hydrogen. The efficient method of suppressing environmental embrittlement of intermetallic is alloying. The moistureinduced environmental embrittlement can be suppressed completely by borondoping in Ni3Al alloy. The basic mechanism of the suppression effect of boron is related to severe reduction of hydrogen diffusivity along the grain boundaries. Effective suppression of the moistureinduced environmental embrittlement by Fedoping in Co3Ti alloy is related to the reduction of the surface reaction kinetic of Co3Ti alloy with water vapor. The H2induced embrittlement can be suppressed completely by boron addition in the ordered Ni3Fe alloy. The suppression mechanism is that boron atom segregates to the grain boundary, reducing the grain size and increasing the mechanical properties of the alloy. Boron in the ordered Ni3Fe alloy clearly increases cohesion of grain boundary and decreases the diffusion coefficient of hydrogen along grain boundary.
Key words: intermetallic, alloying, catalytic reaction, environmental hydrogen embrittlement, hydrogen diffusion, surface reaction
CLC Number:
TG 111
TG 146
CHEN Ye-xin. Environmental Hydrogen Embrittlement of Intermetallics[J]. Journal of Shanghai University(Natural Science Edition), 2011, 17(4): 487-502.
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URL: https://www.journal.shu.edu.cn/EN/10.3969/j.issn.1007-2861.2011.04.016
https://www.journal.shu.edu.cn/EN/Y2011/V17/I4/487