Abstract
Current interest in modeling metal processing using constitutive relations is reliant on precision determination of materials testing parameters. One parameter, the strain rate sensitivity, is extensively quoted, but means to measure it precisely are generally unavailable. The best method to measure this parameter is by intermittent strain rate change tests whereby, in theory, the internal structure is kept constant during the rate change. Conventionally, it is difficult to achieve this constant structure requirement, since the load frame's elastic interaction with the specimen, as well as the specimen's elastic compliance, causes inelastic transients. These transients can be nullified by using the step ramp method and a highly responsive servohydraulic testing system. The implementation of such a method and the evaluation of the measured thermodynamic response is described.
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Carlone, M., Saimoto, S. Precision strain rate sensitivity measurement using the step-ramp method. Experimental Mechanics 36, 360–366 (1996). https://doi.org/10.1007/BF02328579
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DOI: https://doi.org/10.1007/BF02328579