Metallurgical Abstracts on Light Metals and Alloys vol.55

Effect of Electroless Ni-P Plating on Rotary Bending Fatigue Strength of A2017-T4 Aluminum Alloy

Ryohei Shinno*, Makoto Hino*, Ryoichi Kuwano*, Koji Monden**, Masaaki Sato**, Yukinori Oda**, Naoki Fukumuro***, Shinji Yae***, Keitaro Horikawa**** and Teruto Kanadani*****
*Graduate School of Engineering, Hiroshima Institute of Technology
**C.Uyemura & Co., Ltd
***Graduate School of Engineering, University of Hyogo
****Graduate School of Engineering Science, Osaka University
*****Okayama University of Science

[Published in Materials Transactions, Vol. 63 (2022), pp. 872–876]

https://doi.org/10.2320/matertrans.MT-L2022002
E-mail: hino[at]me.it-hiroshima.ac.jp
Key Words: A2017-T4 aluminum alloy, fatigue property, electroless Ni-P Plating, hydrogen embrittlement

In this study, A2017-T4 aluminum alloy was plated with electroless Ni-P with different phosphorus content and rotary bending fatigue test was conducted to investigate the effect of hydrogen by plating on fatigue properties. The fatigue strength of the low-phosphorus type Ni-P plated specimen was higher than that of the untreated specimen, while that of the high-phosphorus type plated specimen was much lower. It is clear that the fatigue strength differs greatly depending on the phosphorus content in the plating film. The decrease in fatigue strength of the high phosphorus type plating specimen was attributed to hydrogen induced by plating from hydrogen analysis. Thus, despite the previous report that 2000 series aluminum alloys do not exhibit hydrogen embrittlement in slow strain rate tensile tests under wet condition, it was found that A2017-T4 aluminum alloy undergo hydrogen embrittlement when the alloy is plated with high-phosphorus type electroless Ni-P and fatigue-tested on rotary bending machine.

Relation between stress amplitude (σa) and number of cycles to failure (N) for the un-treated and electroless Ni-P plated specimens.