Effects of thermal aging on the mechanical properties of type 316 stainless steel - elevated-temperature properties

Charpy impact energy values at room temperature, tensile data collected at the aging temperature, creep data, and room-temperature hardness data on aged type 316 stainless steel were analyzed. Data were derived both from the literature and from our own studies. The aging temperature examined in this study varied from 427 to 816{sup 0}C with aging times up to 90,800 h. Data examined were on block material aged in the laboratory and on material removed after prolonged service in a conventional power plant. The Charpy impact data for various heats aged at ORNL were compared with the time-temperature parameter analysis reported previously. Tensile data for various aging conditions were compared with the minimum property curves for the unaged material. The creep curves were compared for the unaged and aged specimens. Rupture life, minimum creep rate, time to onset of tertiary creep, total elongation, and reduction of area for the aged and unaged specimens were also compared. The creep specimens were also subjected to microstructural analysis. The hardness data on the aged and creep-tested specimens were plotted as a function of aging or creep test time.