The transient data obtained during stress relaxation test of polycrystalline materials has broader implications. The test is influenced by the material length scale. Efforts to mathematically bridge data at different length scales is scarce. In the present work, it is attempted to modify a recently proposed stress relaxation model with additional coefficients to accommodate the mechanical behavior at different length scales. The macroscale stress relaxation test was performed using a tensile testing machine, whereas the micro- and nanoscale specimens were tested using indentation technique. Assuming power law rate behavior, a scaling relation is derived initially to correlate the indentation pressure and flow stress.

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