Tribocorrosion behavior of nickel aluminum bronze in seawater: Identification of corrosion‐wear components and effect of pH

Abstract

This work is focused on the influence of solution pH on the tribocorrosion behavior of a tribosystem between nickel aluminum bronze (NAB) and Al 2 O 3 . To explore the interaction mechanism between wear and corrosion, a pin-on-disc tribometer equipped with a potentiostat was used and the frictional, electrochemical responses were reported in situ during tribocorrosion processes as a function of the solution pH. Results revealed that a high pH solution would aggravate corrosion and give rise to accelerated material loss. In addition, the corrosion mechanism of NAB was dependent on solution pH, that is, the NAB oxidation was driven by the dissolution of Κ II phase at pH below 4.2, whereas its anodic behavior was dominated by the preferential corrosion attack of copper-rich α-phase within the α + Κ III eutectoid when pH was higher than 4.2. Combined with quantitative calculation at various pHs, it was found that the pure mechanical and corrosion-accelerated wear, presented delamination and abrasion, were the main reasons for material degradation. K E Y W O R D Scorrosion, nickel aluminum bronze, synergistic effect, wear

A review of the corrosion behavior of conventional and additively manufactured nickel–aluminum bronze (NAB) alloys: current status and future challenges

“…In one, it was reported that increasing electrolyte pH adversely influenced tribocorrosion response. 121 Corrosion and wear were found to be linked and reinforced each other, leading to higher total tribocorrosion mass loss under experimental conditions. The passive film on the NAB alloy was damaged due to wear, and irregularities such as asperities resulting from induced-plastic deformation made the alloy surface more susceptible to corrosion.…”

“…In the context of tribocorrosion of NABs, the mass loss increased with higher pH values (ranging from 3.2 to 10.2) 121 and lower chloride concentration. 123 As a result, chloride-free solution resulted in the highest mass loss compared to chloride-containing solutions, which was correlated to the lubricating effect of electrolytes in the presence of Cl − ions.…”

“…Initiation and propagation of cracks were also facilitated as a result of exposure to the corrosive solution, promoting wear damage through mechanisms such as abrasion and delamination. 121 In addition, at pH < 4.2, selective phase dissolution of κ IV was detected, whereas at pH > 4.2, dissolution of α-phase within the eutectoid microstructure α + κ III was observed. 121…”

“…121 In addition, at pH < 4.2, selective phase dissolution of κ IV was detected, whereas at pH > 4.2, dissolution of α-phase within the eutectoid microstructure α + κ III was observed. 121…”

Effect of Ti on Microstructure, Mechanical Properties and Corrosion Behavior of a Nickel-Aluminum Bronze Alloy

“…B.-B. Zhang et al 11,12 showed that selective corrosion is highly dependent on the pH and a corrosion wear mechanism was proposed, concluding that the tribocorrosion behavior of NAB alloy in seawater is closely related to the halide-ion concentration.…”