1. Reference problem#

The damage, \(D(t)\), is calculated from the stress tensor data, \(\sigma (t)\), and the cumulative plastic deformation, \(p(t)\).

\(\dot{D}=\frac{1}{{(1-D)}^{\mathrm{2s}}}{\left[\frac{1}{\mathrm{3ES}}(1+\nu ){\sigma }_{\mathrm{eq}}^{2}+\frac{3}{\mathrm{2ES}}(1-2\nu ){\sigma }_{H}^{2}\right]}^{s}\dot{p}\)

if \(p>{p}_{d}\)

\(D=0\)

otherwise

\({\sigma }_{\mathrm{eq}}\) is the equivalent von Mises stress

\({\sigma }_{H}\) is the hydrostatic stress

\({p}_{d}\) represents the damage threshold

\(S\) is a material characteristic (\(\mathrm{MPa}\))

\(s\) is a material characteristic

1.1. Material properties#

\(\mathrm{Temp}(°C)\)

\(E(\mathrm{MPa})\)

\(\nu\)

\(S(\mathrm{MPa})\)

2.E+5

2.E+5

2.E+5

\({p}_{d}=0.02\)

1.1.1. Modeling A#

In this modeling, we check the Lemaître-Sermage damage calculation with respect to the reference solution given in [V9.01.109]. The values of the exponent \(s\) and \(S\) in the expression of generalized Lemaître damage apply to:

\(s=1.0\) and \(S=7.0\)

1.1.2. B modeling#

In this second modeling, the Lemaître-Sermage damage calculation is verified with respect to an analytical solution obtained by applying the algorithms presented in the reference document [R7.04.01]. The values of the exponent \(s\) and \(S\) in the expression of generalized Lemaître damage apply to:

\(s=1.003\) and \(S=7.0\)

1.2. Loading history#

\(t\)

43.11

\({\sigma }_{\mathrm{xx}}(t)\)

\({\sigma }_{\mathrm{yy}}(t)\)

\({\sigma }_{\mathrm{zz}}(t)\)

\({\sigma }_{\mathrm{xy}}(t)\)

\({\sigma }_{\mathrm{xz}}(t)\)

\({\sigma }_{\mathrm{yz}}(t)\)

\(\mathrm{Temp}\)

\(t\)

\(p(t)\) (Cumulative plastic deformation)

43.11

0.019996

0.046384

0.46384

4.6384

9.2768

9.74064

10.20448

10.297248

10.390016