A new sight on the fracture behavior of GH4169 produced by NaCl-induced corrosion in a humid environment of 600 °C

Abstract

A novel fracture mechanism of GH4169 alloy, produced by active corrosion, was proposed via a slow-strain rate test in a NaCl deposition contained 600 °C humid environment. Circular active corrosion accelerates form of Fe, Cr-depletion and Ni-rich region. The region has elevated stacking fault energy and reduced shear modulus, inhibiting the planner slip yet promoting dislocation tangles ahead of the internal corrosion zone. Localized Stress concentration occurs, facilitating crack propagation. The synergistic interplay between cracking and active corrosion processes accelerates the rupture of GH4169 alloy, leading to reduced ductility and tensile strength of GH4169 alloy in the environments.