Austenitic stainless steel and process for removing hydrogen therefrom
AssigneeNational Institute of Advanced Industrial Science and Technology
InventorsYukitaka Murakami, Saburo Matsuoka, Yoji Mine, Toshihiko Kanezaki
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Abstract
By focusing on the non-diffusible hydrogen that causes hydrogen embrittlement of austenitic stainless steel, the present invention provides an austenitic stainless steel in which the non-diffusible hydrogen is removed by maintaining the austenitic stainless steel in a vacuum of 0.2 Pa or less and heating at a heating temperature of 200° C. to 500° C. for 460 hours or less to remove the hydrogen (H) contained therein to a level of 0.00007 mass % (0.7 mass ppm) or less.
Claims12
An austenitic stainless steel having an austenitic phase in which a crystalline structure is a face centered cubic lattice structure,
- wherein diffusible hydrogen and non-diffusible hydrogen, which are cause of hydrogen embrittlement in the austenitic stainless steel, are removed therefrom such that the hydrogen (H) contained in the austenitic stainless steel is removed to a level of 0.00007 mass % (0.7 mass ppm) or less.
A process for removing hydrogen from an austenitic stainless steel, in which the austenitic stainless steel having an austenitic phase in which a crystalline structure is a face centered cubic lattice structure is heat-treated in a heat treatment to remove the hydrogen present in the austenitic stainless steel,
- wherein the austenitic stainless steel is heated to a heating temperature of 200° C. or higher to remove the diffusible hydrogen and non-diffusible hydrogen in the austenitic stainless steel to a level of 0.00007 mass % (0.7 mass ppm) or less.
Dependencies are inferred from the claim text.