The elastic properties of steel at moderately high temperatures

Abstract

In a recent paper the author give the results of measurements of the elastic hysteresis of steel tubes, when subjected to torsional stress, within what is ordinary room temperature, and the chief points established by them were, that the hysteresis of the hard-drawn tubes is much less than that for the same tubes after annealing, and that in the latter case, the loss of energy in the cycle of stress is independent of the speed of performance of the cycle, or, in other words, time is not a factor in the stress-strain relation.. The present research is the outcome of a suggestion by Prof. B. Hopkinson, that at a suitable temperature the hard-drawn tube, which contains a good deal of amorphous material, would begin to behave like a viscous fluid, that is, it would flow more or less freely when under stress, whereas at the same temperature, the annealed tube, being crystalline, though it might take a permanent set, could not flow, or would flow in a much less degree corresponding to the small amount of amorphous material in it.