Stress relaxation of structural steel at high temperatures

Results of a stress relaxation study, which are conducted on three kinds of structural steel, SS41, SM50A and SM58Q, in tension are presented. These specimens were tested under various constant strains from 1000 to 5000 μ (10-6) by 1000 μ increments and at high temperatures from 400 to 6000C by 500C increments for six hours. The stress-strain curves obtained together with stress relaxation curves are shown, and the correlation between stress relaxation behavior and elastic-plastic strain is clarified by these curves. (author)