Fatigue design criteria for pressure vessel steels are developed herein based on analysis of available material data between room temperature and 427 C (800 F). Strain-controlled low-cycle and high-cycle fatigue data for austenitic steels, alloy 800, alloy 600, and alloy 718 were evaluated. The effects of mean stresses were considered and design curves were proposed for use in Sections III and VIII of the ASME Boiler and Pressure Vessel Code.

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This study was undertaken to develop an understanding of the fatigue resistance of AISI 1010 steel under conditions of combined thermal and mechanical strain cycling in air. Comparative evaluations were made with existing thermal-mechanical fatigue data on carbon steels and with results of a comprehensive, companion study of the fatigue behavior of this same steel under isothermal conditions. Thermal-mechanical fatigue behavior was investigated for constant-amplitude, fully reversed, strain cycling of uniaxially loaded specimens at three ranges of temperature: (a) 93 to 316°C (200 to 600°F), (b) 93 to 427°C (200 to 800°F), and (c) 93 to 538°C (200 to 1000°F). Experiments were conducted both with maximum strain in phase with maximum temperature and out of phase with maximum temperature. Considering differences in experimental techniques and the difficulties associated with conducting these types of experiments, the present data agreed with similar data from the literature in limited instances where comparisons could be made. Thus, these results were considered to be representative of this type of steel, and they provided a significant extension of existing knowledge on the thermal-mechanical fatigue resistance of low-carbon steel. Dynamic strain aging was observed to cause more cyclic hardening in these experiments than in isothermal fatigue experiments. In terms of total or plastic strainrange, out-of-phase cycling was more deleterious than in-phase cycling, and thermal-mechanical fatigue life was much less than isothermal fatigue life. However, on the basis of stable stress amplitude, there was little difference in fatigue life between in-phase and out-of-phase cycling, and the fatigue life was reasonably well correlated with isothermal fatigue results.