Metallurgical Abstracts on Light Metals and Alloys vol.56

Suppression of environmental hydrogen embrittlement of Al-Zn-Mg based alloys by means of surface Zinc plating

Keitaro Horikawa*, Hideki Kuwata*, Naoki Fukumuro** and Makoto Hino***
* Department of Mechanical Science and Bioengineering, Osaka University, Toyonaka 560–8531
** Department of Materials Science and Chemistry, Graduate School of Engineering, University of Hyogo, Himeji 671–2280
*** Major in Mechanical Systems Engineering, Graduate School of Science and Technology, Hiroshima Institute of Technology, Hiroshima 731–5193

[Published in Journal of Japan Institute of Metals, Vol. 87 (2023), 108-113]

https://www.jstage.jst.go.jp/article/jinstmet/87/4/87_JC202101/_article/-char/en
E-mail: Horikawa[at]me.es.osaka-u.ac.jp
Key Words: Electro zinc plating, Hydrogen embrittlement, Mechanical properties, Hydrogen absorption, Surface modification

In the present study, the effect of electro zinc plating on environmental hydrogen embrittlement of 7075-T6 aluminum alloys was investigated using a slow strain rate testing device that can detect quantitively the amount of hydrogen generated during deformation and fracture. The testing device can also detect traces of hydrogen gas as low as 5 ppb by using a semiconductor gas sensor at ambient pressure. It was revealed that the environmental hydrogen embrittlement of 7075-T6 aluminum alloys was highly suppressed by zinc-based electroplating, while not fully by anodization. The suppression of the hydrogen embrittlement by zinc plating was caused by the protection of original aluminum surfaces during plastic deformation.

Hydrogen release during SSRT of 7075-T6 aluminum alloys (a): Zn-plating (wet), (b): anodized (wet).