Numerical study of the viscoelastic mechanical response of polystyrene in the process of thermoforming through the generalized Maxwell model

Sánchez, Esteban; Nájera, Arturo; Sotomayor, Oscar

doi:10.1016/j.matpr.2021.07.480

Cited by 7 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, the viscoelastic properties may be influenced by the fillers [5,6] or blending of different thermoplastics [7]. At low stress levels, the polymers are well-described by linear viscoelasticity, like generalized Maxwell models, which were applied to, e.g., polyamide [8] or polystyrene [9]. At higher stress levels, nonlinear viscoelastic effects become apparent in some materials, e.g., polypropylene [10].…”

Section: State Of the Artmentioning

confidence: 99%

Accounting for viscoelastic effects in a multiscale fatigue model for the degradation of the dynamic stiffness of short-fiber reinforced thermoplastics

et al. 2022

View full text Add to dashboard Cite

Under fatigue loading, the stiffness decrease in short-fiber reinforced polymers reflects the gradual degradation of the material. Thus, both measuring and modeling this stiffness is critical to investigate and understand the entire fatigue process. Besides evolving damage, viscoelastic effects within the polymer influence the measured dynamic stiffness. In this paper, we study the influence of a linear viscoelastic material model for the matrix on the obtained dynamic stiffness and extend an elastic multiscale fatigue-damage model to viscoelasticity. Our contribution is two-fold. First, we revisit the complex-valued elastic models known in the literature to predict the asymptotic periodic orbit of a viscoelastic material. For small phase shifts in an isotropic linear viscoelastic material, we show through numerical experiments that a real-valued computation of an “elastic” material is sufficient to approximate the dynamic stiffness of a microstructure with a generalized Maxwell material and equal Poisson’s ratios in every element as matrix, reinforced by elastic inclusions. This makes standard solvers applicable to fiber-reinforced thermoplastics. Secondly, we propose a viscoelastic fatigue-damage model for the thermoplastic matrix based on decoupling of the time scales where viscoelastic and fatigue-damage effects manifest. We demonstrate the capability of the multiscale model to predict the dynamic stiffness evolution under fatigue loading of short-fiber reinforced polybutylene terephthalate (PBT) by a validation with experimental results.

show abstract

Section: State Of the Artmentioning

confidence: 99%

Accounting for viscoelastic effects in a multiscale fatigue model for the degradation of the dynamic stiffness of short-fiber reinforced thermoplastics

et al. 2022

View full text Add to dashboard Cite

show abstract

“…The results of punching force and sheet thickness estimated by the model were validated experimentally. A viscoelastic model was developed by Sánchez et al [15], where the authors used the generalized Maxwell model. The model was implemented in Abaqus using Prony series parameters to replicate the thermoforming processes for polystyrene material under external loads and specific conditions of time and temperature.…”

Section: Introductionmentioning

confidence: 99%

Modeling the Thermoforming Process of a Complex Geometry Based on a Thermo-Visco-Hyperelastic Model

Ragoubi,

Ducloud,

Agazzi

et al. 2024

JMMP

View full text Add to dashboard Cite

The thermoforming process is commonly used in industry for the manufacturing of lightweight, thin-walled products from a pre-extruded polymer sheet. Many simulations have been developed to simulate the process and optimize it with computer tools. The development of testing machines has simplified the simulation of this type of process, allowing researchers to characterize the behavior of the material at different temperatures and for large deformation to be closer to the real conditions of the process. This paper presents the results of a study on the modeling of the thermoforming process for an industrial demonstrator made from a high-impact polystyrene (HIPS) polymer. The HIPS shows a mechanical behavior that depends on the temperature and strain rate. In such conditions, a thermo-hyper-viscoelastic constitutive model is used to replicate the thermoforming process of the industrial demonstrator using ABAQUS/Explicit. Its behavior is determined via various experimental tests: uniaxial tensile tests at different temperatures and strain rates and Dynamic Mechanical Analysis (DMA). A comparison between the numerical and experimental results is carried out for the evolution of film thickness. The paper concludes with a discussion of possible improvements to be considered for future simulations of the thermoforming process using Abaqus, which presents complex challenges in terms of contact and material modeling.

show abstract

Experimental and numerical investigation of the effects of sheet material, plug-assist tool material, and process conditions on the mechanical pre-stretching stage of plug-assist thermoforming

Atmani

Abbès

et al. 2022

Int J Adv Manuf Technol

View full text Add to dashboard Cite

Numerical study of the viscoelastic mechanical response of polystyrene in the process of thermoforming through the generalized Maxwell model

Cited by 7 publications

References 14 publications

Accounting for viscoelastic effects in a multiscale fatigue model for the degradation of the dynamic stiffness of short-fiber reinforced thermoplastics

Accounting for viscoelastic effects in a multiscale fatigue model for the degradation of the dynamic stiffness of short-fiber reinforced thermoplastics

Modeling the Thermoforming Process of a Complex Geometry Based on a Thermo-Visco-Hyperelastic Model

Experimental and numerical investigation of the effects of sheet material, plug-assist tool material, and process conditions on the mechanical pre-stretching stage of plug-assist thermoforming

Contact Info

Product

Resources

About