Study on Stress Corrosion Sensitivity of 316L Stainless Steel in Medium Enviornment Containing Cl^- and CH₃COOH

Abstract

At present, there are few studies on the stress corrosion sensitivity of 316L stainless steel in the environment containing Cl- and CH3COOH. In this paper, the effects of Cl- and CH3COOH on the stress corrosion sensitivity of 316L stainless steel were studied by slow strain rate tensile test, scanning electron microscopy (SEM) and X - ray photoelectron spectroscopy (XPS). Results showed that when the concentration of Cl- was higher than 2 000 mg/L, the stress corrosion tendency of 316L stainless steel was obvious, and the stress corrosion sensitivity of 316L stainless steel increased with an increasing rate while the Cl- concentration rised. Under the condition of low concentration of Cl-, CH3COOH could exacerbate stress corrosion. When the concentration of Cl- reached 1 000 mg/L, CH3COOH could inhibit stress corrosion. The XPS results revealed that CH3COOH could change the composition of 316L stainless steel passivation film and then improve its corrosion resistance.

Keywords

• 316l stainless steel|cl-|ch3cooh|stress corrosion