Austenitic stainless steel surfacing is commonly used to protect ferritic pressure vessels from the corrosive environment in nuclear reactors and chemical process plants. The delta ferrite in a Nb-stabilized austenitic cladding decomposes during stress relief heat treatments (10 to 600 h at 670 degree C, or 1238 degree F), forming sigma phase and secondary austenite. Increases in sigma phase content enhance hydrogen embrittlement and reduce impact toughness. Slow strain-rate tests did not cause stress corrosion cracking in hot 0. 58N H//3BO//3 solution. In 1N HCl solution the cracks grew as the delta ferrite and sigma phases were selectively dissolved.
|Number of pages||9|
|Publication status||Published - Jan 1984|
|MoE publication type||A1 Journal article-refereed|