Fatigue Property of Electroless Ni–P Plated A7075-T6511 Alloy Affected by Plated Film Composition

Abstract

In this study, with the aim of improving the fatigue characteristics of the A7075 aluminum alloy, A7075-T6511 alloy rod specimens were plated with electroless Ni–P with different compositions, and the fatigue characteristics were evaluated by a rotary bending fatigue test. The fatigue strength of the specimen plated with low-P type was higher than that of the un-plated specimen. However, the fatigue strength of the specimen plated with high-P type was significantly lower than that of the un-plated specimen, and the fatigue strength of the specimen plated with medium-P type was also lower though the extent was not so significant. It was speculated that these reductions in fatigue strength were due to hydrogen embrittlement by the hydrogen introduced into the specimen during the plating.

 

This Paper was Originally Published in Japanese in J. JILM 71 (2021) 534–538.

Fig. 4 Relation between stress amplitude (σ_a) and number of cycles to failure (N) for the four types of specimens.