Influence of surface modifications on pitting corrosion behavior of nickel-base alloy 718. Part 1: Effect of machine hammer peening

• DOI: 10.1016/j.corsci.2013.08.007
• Publication Date: 2013-08-17T01:15:12Z
• Authors: Ting Chen; Hendrik John; Jing Xu; Qiuhong Lu; Jeffrey Hawk; Xingbo Liu
• Keywords: Pitting Corrosion; Hammer; Crevice corrosion; Work hardening

Abstract The effect of surface modifications induced by machine hammer peening on pitting corrosion behavior of nickel-base alloy 718 in a 3.5 wt.% NaCl solution is investigated. Severe work hardening and high compressive residual stress are generated with surface smoothing and microstructure evolution in terms of formation of nano-grains and nano-twins in the near surface region after machine hammer peening. Electrochemical tests results show that machine hammer peening has a beneficial influence on the corrosion resistance, indicated by a significant increase of the critical pitting potential (+134 mV) accompanied with lower corrosion current density and higher polarization resistance.