Determination of the strain rate sensitivity of a superplastic material at constant load test

Integration of graphene in poly(lactic) acid by 3D printing to develop creep and wear‐resistant hierarchical nanocomposites

“…For which represents the instantaneous depth of the indenter and represents the rate of change of indentation depth. Computation of the strain‐rate sensitivity index ( m ) for viscoelastic materials obeys the power law assuming a steady‐state process has been approximated : where σ represents the stress experienced by the constant load applied over the projected area of the indenter, is the strain‐rate, m is the strain‐rate sensitivity index and C represents a dynamic modulus. Index values obtained represent the capability of the material to resist plastic deformation, while denoting its dependence in the molecular structure of the specimens .…”

“…For which h represents the instantaneous depth of the indenter and dh=dt represents the rate of change of indentation depth. Computation of the strain-rate sensitivity index (m) for viscoelastic materials obeys the power law assuming a steady-state process has been approximated [32,35]:…”

Modelling and tracing the super plastic deformation process of 7075aluminium alloy sheet: use of finite element technique

“…In practice, superplasticity conditions are summarised as a grain size less than 10 lm, low strain rate of less than 10 À3 s À1 and at temperatures of P 0.5 T m , where T m is the melting point of the material [4]. The main application fields of this process are automobile and aircraft industries because of its superior characteristics, such as lightweight, low cost and short fabrication time [5][6][7][8][9][10].…”

Determination of material parameters for 7475 Al alloy from bulge forming tests at constant stress

“…The uniaxial tensile test is still the most commonly used method for determining superplastic material parameters; its advantage being due to its simplicity in testing and cost [6][7][8]. Most of the works on the numerical analysis of superplastic forming have been concerned with constant material characteristics m and K obtained from uniaxial tensile test [9][10][11].…”