Influence of Hydrogen on Stress Corrosion Behavior of Austenitic Stainless Steel

Abstract

In order to investigate the behaviors of hydrogen embrittlement and stress corrosion cracking in austenitic stainless steel, the change in ductility of 18Cr-8Ni steel under various environments was studied chiefly by means of 180°repetition bending test.
The main results obtained are as follows:
(1) The hydrogen embrittlement in austenitic stainless steel was determined sensitively by the bending test after pickling and electrolysis.
(2) It was found that the steel also embrittled during stress corrosion test in boiling 42 percent magnesium chloride solution and took a process analogous to that of hydrogen embrittlement by pickling and electrolysis.
(3) The hydrogen occlusion owing to various environments occured only near the surface layer, and the recovery of ductility was limited at the initiation period of the embrittlement and the longer exposure time made the more embrittlement.
(4) It was concluded that the hydrogen embrittlement plays an important role in the formation of the susceptible paths for the stress corrosion cracking of austenitic stainless steel.