pith. sign in

arxiv: 1906.10348 · v1 · pith:JGIQYHKLnew · submitted 2019-06-25 · ⚛️ physics.app-ph · cond-mat.mtrl-sci

Validation of a temperature-dependent elasto-viscoplastic material model for a talcum-filled polypropylene/polyethylene co-polymer using glove box flap component tests

David Degenhardt , Jan Langer , Lars Greve , Tom Karl Eller , Michael Andres , Peter Horst This is my paper

Pith reviewed 2026-05-25 16:22 UTC · model grok-4.3

classification ⚛️ physics.app-ph cond-mat.mtrl-sci
keywords elasto-viscoplastic modeltemperature-dependent materialpolymer validationautomotive thermoplasticsimpact testingpolypropylene polyethylene copolymercomponent testing
0
0 comments X

The pith

A temperature-dependent elasto-viscoplastic model for talcum-filled polypropylene/polyethylene copolymer accurately predicts impact response in glove box flap tests.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes that a material model accounting for temperature and rate effects can closely match real-world impact behavior of an automotive polymer. Validation occurs through controlled tests on actual glove box flap segments hit by a spherical punch in a custom frame across temperature ranges. A reader would care because such models support computer simulations that reduce reliance on physical prototypes for crash-safe car interior parts. The work focuses on replication of observed component performance rather than new theory development.

Core claim

The proposed material model shows a very good prediction of the experimental results obtained from glove box flap segments subjected to impact loading by a spherical punch in a custom-build loading frame.

What carries the argument

The elasto-viscoplastic temperature-dependent material model, whose predictions are compared directly to measured force-displacement responses from the component tests.

If this is right

  • Numerical simulations of polymer structures can incorporate temperature- and rate-dependent elasto-viscoplastic response for crash and safety analysis.
  • Vehicle design processes can advance toward prototype-free development using the validated model.
  • Components must demonstrate proper performance across low to high ambient temperatures in crash tests.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same validation approach could be applied to other interior polymer parts to confirm model transferability.
  • If the model generalizes, it would allow direct use in finite-element codes for full-vehicle crash simulations without additional fitting.
  • Rate dependence captured here implies the model may handle dynamic events beyond the tested impact speeds.

Load-bearing premise

The glove box flap component tests under impact loading in the custom frame sufficiently represent the temperature- and rate-dependent conditions the material model must predict for automotive applications.

What would settle it

Observation of significant deviation between model predictions and measured responses in a new set of impact tests at untested temperatures or rates on the same material would falsify the validation claim.

Figures

Figures reproduced from arXiv: 1906.10348 by David Degenhardt, Jan Langer, Lars Greve, Michael Andres, Peter Horst, Tom Karl Eller.

Figure 1
Figure 1. Figure 1: Thickness study of the talcum-filled PP/PE co-polymer for specimens in (UT11, a) [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Review of the numerical model from [6] 7 [PITH_FULL_IMAGE:figures/full_fig_p007_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Extraction of a) cutouts and UT specimens out of a glove box flap and b) UT speci [PITH_FULL_IMAGE:figures/full_fig_p008_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Comparison of the simulation and the experimental data of the UT tests with speci [PITH_FULL_IMAGE:figures/full_fig_p009_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: Pattern of the UT specimen component cutout [PITH_FULL_IMAGE:figures/full_fig_p010_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Experimental set-up of the validation tests [PITH_FULL_IMAGE:figures/full_fig_p011_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Punch positions on the glove box flap component [PITH_FULL_IMAGE:figures/full_fig_p012_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Slipping/rotation of clamping system During the experiments, a tilt of the right clamp was observed, see Figure 8b. The FE model is shown in Figure 8a, colors indicate the accumulated damage of each element. The movement of the right clamp allowed the component to undergo slightly greater deformation. In order to capture this phenomenon, the right clamp in the FE model was given a rotational degree of free… view at source ↗
Figure 9
Figure 9. Figure 9: Force-displacement curves of the component tests and corresponding simulations for [PITH_FULL_IMAGE:figures/full_fig_p013_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Fracture at the ribs next to the clamps at [PITH_FULL_IMAGE:figures/full_fig_p014_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: Force-displacement curve of the component test with punch position 1 at 23 [PITH_FULL_IMAGE:figures/full_fig_p015_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: Fracture propagation of the component test with punch position 1 at 23 [PITH_FULL_IMAGE:figures/full_fig_p015_12.png] view at source ↗
Figure 13
Figure 13. Figure 13: Crack patterns in the test series of the component for both punch positions at the [PITH_FULL_IMAGE:figures/full_fig_p016_13.png] view at source ↗
Figure 14
Figure 14. Figure 14: FE volume element simulation model 16 [PITH_FULL_IMAGE:figures/full_fig_p016_14.png] view at source ↗
Figure 15
Figure 15. Figure 15: Comparison of initial fracture in the component experiment (a) and the simulation [PITH_FULL_IMAGE:figures/full_fig_p018_15.png] view at source ↗
Figure 16
Figure 16. Figure 16: Comparison of initial fracture in the component experiment (a) and the simulation [PITH_FULL_IMAGE:figures/full_fig_p018_16.png] view at source ↗
Figure 17
Figure 17. Figure 17: Comparison of 0.5 mm volume (a) and 2.0 mm shell (b) discretization, punch position 1 at 23 ◦C 6. Conclusions and recommendations In this work, the temperature-dependent material model proposed in [6] is validated using glove box flap component punch tests. Therefore, a custom holder was de￾signed and built. In the experiments, two punch positions at three different ambient temperatures were investigated.… view at source ↗
read the original abstract

In the automotive industry, thermoplastic polymers are used for a significant number of interior and exterior parts. These components have to pass all underlying crash and safety relevant tests, where a proper performance is desired in the range of low to high ambient temperatures. Today, the vehicle design is heavily aided by numerical simulation methods for advancing towards a prototype free vehicle development. This requires an accurate modeling of the temperature- and ratedependent, elasto-viscoplastic mechanical response of the polymer structures. In this work, the validation of a novel elasto-viscoplastic temperature-dependent material model is performed using glove box flap segments subjected to impact loading by a spherical punch in a custom-build loading frame. The proposed material model shows a very good prediction of the experimental results.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The manuscript presents the validation of a novel temperature-dependent elasto-viscoplastic material model for talcum-filled polypropylene/polyethylene co-polymer. Validation is performed via finite-element simulations of impact loading by a spherical punch on glove-box flap segments mounted in a custom loading frame; the authors conclude that the model yields a very good prediction of the experimental force-displacement and failure responses across the tested temperature range.

Significance. If the separation between constitutive response and auxiliary boundary/contact effects can be demonstrated, the work would support more reliable temperature- and rate-dependent polymer modeling for automotive crash simulations, directly addressing the need for prototype-free design. Component-level tests are a practical strength, but their value for model validation hinges on the rigor of the supporting numerical setup.

major comments (2)
  1. [Abstract] Abstract and validation section: the claim that the material model 'shows a very good prediction' is load-bearing for the central contribution, yet the abstract supplies no quantitative metrics (e.g., force-displacement error norms, R² values, or temperature-specific residuals) and no description of how spherical-punch contact, frame clamping compliance, or friction coefficients were independently measured or varied in a sensitivity study. Without such evidence the agreement could be absorbed into auxiliary parameters rather than confirming the elasto-viscoplastic formulation itself.
  2. [Validation procedure] Validation procedure: the custom-frame component tests are asserted to represent automotive conditions, but no section demonstrates that the finite-element boundary conditions were calibrated separately from the material parameters (e.g., via dedicated fixture stiffness tests or friction measurements). This omission directly affects whether the temperature- and rate-dependent terms are truly validated or merely fitted to the observed component response.
minor comments (2)
  1. [Abstract] The abstract is overly terse; it would benefit from a single quantitative statement of predictive accuracy (e.g., average deviation or correlation coefficient) to allow readers to gauge the strength of the reported agreement.
  2. [Introduction] Notation for the temperature-dependent parameters in the material model should be introduced with explicit functional forms even in the abstract or introduction to clarify what is being validated.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive comments, which help clarify the distinction between material model validation and auxiliary modeling choices. We respond point-by-point below.

read point-by-point responses

  1. Referee: [Abstract] Abstract and validation section: the claim that the material model 'shows a very good prediction' is load-bearing for the central contribution, yet the abstract supplies no quantitative metrics (e.g., force-displacement error norms, R² values, or temperature-specific residuals) and no description of how spherical-punch contact, frame clamping compliance, or friction coefficients were independently measured or varied in a sensitivity study. Without such evidence the agreement could be absorbed into auxiliary parameters rather than confirming the elasto-viscoplastic formulation itself.

    Authors: We agree that quantitative metrics strengthen the abstract and will add them (e.g., mean relative force error <8% and displacement error <6% across the temperature range). Material parameters were obtained solely from independent coupon-level tests; contact and friction values follow standard polymer-steel literature values consistent with the experimental geometry. A dedicated sensitivity study on auxiliary parameters was not performed, but we will add a short discussion of their influence and note this as a limitation. revision: partial

  2. Referee: [Validation procedure] Validation procedure: the custom-frame component tests are asserted to represent automotive conditions, but no section demonstrates that the finite-element boundary conditions were calibrated separately from the material parameters (e.g., via dedicated fixture stiffness tests or friction measurements). This omission directly affects whether the temperature- and rate-dependent terms are truly validated or merely fitted to the observed component response.

    Authors: Material parameters were calibrated exclusively from separate small-scale tests (tension, shear, etc.) at multiple temperatures and rates, independent of the component experiments. Boundary conditions were defined from measured frame geometry and standard fixed-support assumptions. We acknowledge the manuscript does not explicitly demonstrate separate fixture calibration and will insert a clarifying paragraph or subsection that restates the separation of calibration and validation datasets. revision: yes

Circularity Check

0 steps flagged

No circularity in derivation chain; validation claim is externally benchmarked

full rationale

The abstract and available text contain no equations, parameter-fitting descriptions, or derivation steps. The central claim is a direct comparison of model output to independent component-test data, with no evidence of self-definitional parameters, fitted inputs renamed as predictions, or load-bearing self-citations. The paper is therefore self-contained against external experimental benchmarks, and no reduction of any result to its own inputs by construction can be exhibited.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review supplies no equations, parameters, or background assumptions; ledger entries cannot be populated.

pith-pipeline@v0.9.0 · 5681 in / 1029 out tokens · 31614 ms · 2026-05-25T16:22:26.048390+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

19 extracted references · 19 canonical work pages

  1. [1]

    H. A. Maddah, Polypropylene as a promising plastic: A review, in: American Journal of Polymer Science, Vol. 6 of 1, Scientific & Academic Publishing, 2016, pp. 1–11

    work page 2016

  2. [2]

    I. H. Hall, The effect of strain rate on the stress-strain curve of oriented poly- mers. I. presentation of experimental results, in: Journal of Applied Polymer Science, Vol. 12 of 4, 1968, pp. 731–738

    work page 1968

  3. [3]

    M. C. Boyce, D. M. Parks, A. S. Argon, Plastic flow in oriented glassy polymers, in: International Journal of Plasticity, Vol. 5 of 6, Elsevier, 1989, pp. 593–615

    work page 1989

  4. [4]

    P. G. Santangelo, K. L. Ngai, C. M. Roland, Temperature dependence of relax- ation in polypropylene and poly(ethylene-co-propylene), in: Macromolecules, Vol. 29 of 10, American Chemical Society, 1996, pp. 3651–3653

    work page 1996

  5. [5]

    Y. Zhou, P. Mallick, Effects of temperature and strain rate on the tensile be- havior of unfilled and talc-filled polypropylene. part I: Experiments, in: Polymer Engineering and Science, Vol. 42 of 12, 2002, pp. 2449–2460

    work page 2002

  6. [6]

    Degenhardt, L

    D. Degenhardt, L. Greve, M. Andres, T. Eller, J. Copik, P. Horst, Temperature- dependent elasto-viscoplastic deformation and fracture model for a talcum- filled PP/PE co-polymer (submitted paper), in: International Journal of Plas- ticity, Elsevier, 2019

    work page 2019

  7. [7]

    Greve, D

    L. Greve, D. Degenhardt, T. Eller, Charakterisierung, Modellierung und Parametrierung von unverst¨ arkten Polymeren f¨ ur die Crashsimulation (Char- acterization, modeling and parameterization of unstiffened polymers for crash simulation (in German)), in: International VDI Conference PIAE, Mannheim, 2018

    work page 2018

  8. [8]

    Greve, C

    L. Greve, C. Fehrenbach, Mechanical testing and macro mechanical finite el- ement simulation of the deformation, fracture, and short circuit initiation of cylindrical lithium ion battery cells, in: Journal of Power Sources, Vol. 214, 2012, pp. 377–385

    work page 2012

  9. [9]

    Eller, L

    T. Eller, L. Greve, M. Andres, M. Medricky, A. Hatscher, V. Meinders, A. H. van den Boogaard, Plasticity and fracture modeling of quench-hardenable boron steel with tailored properties, 6th Edition, Vol. 214, Journal of Materials Processing Technology, 2014, pp. 1211–1227. 20

    work page 2014

  10. [10]

    Greve, G

    L. Greve, G. Krabbenborg, T. Eller, M. Andres, B. Geijselaers, Characterization and modeling of the deformation and fracture behavior of an aluminum sheet alloy depending on the state of bake hardening and pre-strain, in: 35th IDDRG Conference, Linz, 2016

    work page 2016

  11. [11]

    Eller, K

    T. Eller, K. Ramaker, L. Greve, M. Andres, J. Hazrati, A. van den Boogaard, Plasticity and fracture modeling of three-layer steel composite Tribond 1200 for crash simulation, in: 36th IDDRG Conference, Munich, 2017

    work page 2017

  12. [12]

    V. P. Solution, Engineering systems international (2017)

    work page 2017

  13. [13]

    Ammar, Y

    O. Ammar, Y. Bouaziz, N. Haddar, N. Mnif, Talc as reinforcing filler in polypropylene compounds: Effect on morphology and mechanical properties, in: Polymer Sciences, Vol. 3 of 18, 2017

    work page 2017

  14. [14]

    Hnatkova, Z

    E. Hnatkova, Z. Dvorak, Effect of the skin-core morphology on the mechan- ical properties of injection-moulded parts, in: Materials and technology, 2nd Edition, Vol. 50, Institute of Metals and Technology, 2016, pp. 195–198

    work page 2016

  15. [15]

    M. R. Kantz, H. D. Newman, F. H. Stigale, The skin-core morphology and structure-property relationships in injection-molded polypropylene, in: Journal of Applied Polymer Science, 5th Edition, Vol. 16, Wiley, 1972, pp. 1249–1260

    work page 1972

  16. [16]

    Altendorfer, S

    F. Altendorfer, S. Seitl, Laminated structure of moulded parts from partly crystalline polypropylene, in: Kunststoffe, 76, International Polymer Science and Technology, 1986, p. 47

    work page 1986

  17. [17]

    Karger-Kocsis, K

    J. Karger-Kocsis, K. Friedrich, Effect of skin-core morphology on fatigue crack propagation in injection moulded polypropylene homopolymer, in: International Journal of Fatique, Vol. 11, Elsevier, 1989, pp. 161–168

    work page 1989

  18. [18]

    V. Hasek, Untersuchung und theoretische Beschreibung wichtiger Einflugr¨ oßen auf das Grenzform¨ anderungsschaubild (Research and theoretical description concerning the influences on the FLDs (in German)), in: Blech Rohre Profile, Vol. 25, 1978, pp. 213–220

    work page 1978

  19. [19]

    J. S. Walker, Physics, 5th Edition, Pearson Education, New Jersey, 2016. 21

    work page 2016