Creep–fatigue–oxidation interactions in a 9Cr–1Mo martensitic steel. Part I: Effect of tensile holding period on fatigue lifetime

Cyclic tests with or without tensile holding periods were conducted in air at 823 K on a modified 9Cr–1Mo martensitic steel. In addition to stress–relaxation fatigue (RF) tests with a hold time at maximum load, creep–fatigue (CF) experiments were carried out. These CF tests were strain-controlled during the cyclic part of the stress–strain hysteresis loop and then load controlled when the stress was maintained at its maximum value to produce a...