High Temperature Rupture, Fatigue, and Damping Properties of AISI Designation 616 (Type 422 Stainless) Steel

This paper covers the high temperature rupture, fatigue, and damping properties of AISI Designation 616 (Type 422) steel conforming substantially to the requirements of ASTM specification A437 grade B4C. This material has been extensively used for boiling and for steam turbine blading for service in the temperature range of 850 to 1000 F. The results of stress rupture and fatigue tests of smooth and notched bars at 800, 950, and 1050 F are presented. Stress rupture tests extend to 2000 hr or more and fatigue tests generally extend to 2 × 10⁷ cycles or about 100 hr. The fatigue tests were performed in a direct stress machine at stress ratios A = infinity, 2.5, and 1.0. Vibration decay damping tests with various mean stresses were performed at 75, 800, 950, and 1050 F.