Table 1 Fitting of creep compliance J(t) with different rheological models.
Model | J(t) | Parameters | R 2 |
|---|---|---|---|
Fractional Maxwell model | \(\frac{1}{{E}_{{\rm{H}}}}+\frac{1}{{\eta }_{{\rm{A}}}^{\alpha }}\frac{{t}^{\alpha }}{{\rm{\Gamma }}(1+\alpha )}\) | E H = 4.426 GPa | 0.99 |
\({\eta }_{{\rm{A}}}^{\alpha }=219.562\,{\rm{GPa}}\cdot {s}^{\alpha }\) | |||
α = 0.268 | |||
Maxwell model | \(\frac{1}{{E}_{{\rm{H}}}}+\frac{t}{{\eta }_{{\rm{N}}}}\) | \({E}_{{\rm{H}}}=3.944\,{\rm{GPa}}\) | 0.99 |
\({\eta }_{{\rm{N}}}=2.375\times {10}^{5}\,{\rm{GPa}}\cdot {\rm{s}}\) | |||
Three-parameter generalized Kelvin model | \(\frac{1}{{E}_{{\rm{H}}}}+\frac{1}{{E}_{{\rm{K}}}}[1-\exp (-\frac{{E}_{{\rm{K}}}}{{\eta }_{{\rm{K}}}}t)]\) | \({E}_{{\rm{H}}}=4.078\,{\rm{GPa}}\) | 0.99 |
\({E}_{{\rm{K}}}=27.741\,{\rm{GPa}}\) | |||
\({\eta }_{{\rm{K}}}=7.481\times {10}^{4}\,{\rm{GPa}}\cdot {\rm{s}}\) | |||
Burgers model | \(\frac{1}{{E}_{{\rm{H}}}}+\frac{t}{{\eta }_{{\rm{N}}}}+\frac{1}{{E}_{{\rm{K}}}}[1-\exp (-\frac{{E}_{{\rm{K}}}}{{\eta }_{{\rm{K}}}}t)]\) | \({E}_{{\rm{H}}}=4.135\,{\rm{GPa}}\) | 0.99 |
\({E}_{{\rm{K}}}=49.254\,{\rm{GPa}}\) | |||
\({\eta }_{{\rm{N}}}=3.896\times {10}^{5}\,{\rm{GPa}}\cdot {\rm{s}}\) | |||
\({\eta }_{{\rm{K}}}=4.667\times {10}^{4}\,{\rm{GPa}}\cdot {\rm{s}}\) |
