Reference revision · 2026-09-27
Prepreg 03 and 05 use eight 0.125 mm T700/PEEK plies, [0/90]2s. Run these examples to see melt flow, voids, intimate contact and healing across all seven interfaces. Prepreg 01, 02 and 04 use thermoset epoxy with cure and CHILE stiffness; thermoplastic healing is disconnected.
Open the PEEK material to edit its Resin viscosity model and Viscoelastic modulus model. In the thermal case, Initial conditions selects Void consolidation, Intimate contact, Interface bonding and Material model sampling. Roller force produces the shared pressure through all plies.
Thermal results offer melt viscosity, flow-active state, SLS matrix modulus, SLS unit-step relaxation and lamina E1/E2/G12. Select interfaces or plies in the material-state plots to inspect bonding and voids.
Thermoplastic Arrhenius melt viscosity
| Model family | Thermoplastic Arrhenius melt viscosity model |
|---|---|
| Melt viscosity prefactor | 0.016384 Pa·s |
| Melt viscosity coefficient | 6403 K |
| Melt viscosity offset | 30 K |
| Melt flow activation temperature | 343 °C |
| Viscosity reporting ceiling | 1000000000000 Pa·s |
| Formulation | eta = A exp[B/(T[K]+C)]. Flow pauses at/below activation temperature; solid-state ceiling is reporting only. |
| Parameter basis | PEEK example flow law retained from the existing void-cell example. Using it for interface squeeze flow is a teaching assumption requiring surface-specific calibration. |
| Source | https://doi.org/10.1016/j.compositesa.2012.10.015 |
| Assumptions | Zero-shear temperature law. No cure, shear thinning, degradation or crystallinity feedback. Melt viscosity is independent of the SLS dashpot viscosity. |
Thermoplastic standard linear solid
| Model family | Thermoplastic standard linear solid model |
|---|---|
| Instantaneous resin modulus | 3.6 GPa |
| Equilibrium resin modulus | 0.0036 GPa |
| Reference relaxation time | 10 s |
| Relaxation reference temperature | 143 °C |
| Relaxation activation energy | 100 kJ/mol |
| Modulus observation time | 1 s |
| Formulation | E(t,T)=Einf+(E0-Einf) exp[-t/tau(T)]; tau(T)=tauRef exp[Ea/R(1/T-1/Tref)]. |
| Parameter basis | Illustrative PEEK-like relaxation spectrum; fit E0, Einf, tau and temperature shift to measured DMA/relaxation data. Not a grade calibration. |
| Assumptions | Thermorheologically simple SLS with constant branch springs and Poisson ratio. Nonzero equilibrium modulus is a solid approximation, not a molten-fluid law. Micro/CLT use observation-time modulus; thermal stresses are equivalent-elastic, not a hereditary laminate stress solve. Unit-step relaxation is also reported. |
| Source | https://doc.comsol.com/6.3/doc/com.comsol.help.sme/sme_ug_theory.06.029.html |
SLS is an equilibrium spring in parallel with one Maxwell branch. It predicts E(t,T) = Einf + (E0 − Einf) exp(−t/τ(T)). The explicit observation time sets the stiffness used by micromechanics and equivalent-elastic thermal CLT. It is independent of the thermal output interval. The separate unit-step relaxation plot integrates reduced time along the thermal history.
This release does not solve full hereditary laminate stresses, crystallization feedback, melt latent heat or degradation. The SLS equilibrium spring approximates a soft solid; melt-flow viscosity is a separate law. All new material coefficients are editable teaching inputs, not certified PEEK data.
SLS and temperature-shift formulation