Simulation of thermoplastic prepreg thermoforming based on a visco-hyperelastic model and a thermal homogenization

Guzman-Maldonado, E.; Hamila, Nahiene; Naouar, Naïm; Moulin, Gabrielle; Boisse, Philippe

doi:10.1016/j.matdes.2015.12.166

Cited by 114 publications

(46 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are several possible explanations for this. As is consistent with other work in the field [57], the model does not take into account the viscoelastic nature of the material response to loading in the direction of the fibers [58,59]. Only the timeindependent part of the response to bending of the prepreg is taken into consideration and this may result in an overly stiff behavior.…”

Section: Identification Of Wrinkles Formation Mechanismmentioning

confidence: 66%

Consolidation-Driven Defect Generation in Thick Composite Parts

Belnoue

Nixon-Pearson

Thompson

et al. 2018

Journal of Manufacturing Science and Engineering

View full text Add to dashboard Cite

Fiber waviness is one of the most significant defects that occurs in composites due to the severe knockdown in mechanical properties that it causes. This paper investigates the mechanisms for the generation of fiber path defects during processing of composites prepreg materials and proposes new predictive numerical models. A key focus of the work was on thick sections, where consolidation of the ply stack leads to out of plane ply movement. This deformation can either directly lead to fiber waviness or can cause excess fiber length in a ply that in turn leads to the formation of wrinkles. The novel predictive model, built on extensive characterization of prepregs in small-scale compaction tests, was implemented in the finite element software ABAQUS as a bespoke user-defined material. A number of industrially relevant case studies were investigated to demonstrate the formation of defects in typical component features. The validated numerical model was used to extend the understanding gained from manufacturing trials to isolate the influence of various material, geometric, and process parameters on defect formation.

show abstract

Section: Identification Of Wrinkles Formation Mechanismmentioning

confidence: 66%

Consolidation-Driven Defect Generation in Thick Composite Parts

Belnoue

Nixon-Pearson

Thompson

et al. 2018

Journal of Manufacturing Science and Engineering

View full text Add to dashboard Cite

show abstract

“…The same effect can be observed on differential scanning calorimetry diagrams as the offset between the endo-and exothermic peaks of melting and crystallization, respectively. The effect is due to thermal inertia, since the endothermic physical reaction of crystal melting is taking up extra thermal energy while the exothermic crystallization is heating the material from the inside [3]. This discrepancy was determined separately for both Tepex and Ultratape materials based on the DMA storage modulus curves, as seen in Fig.…”

Section: Dma Experimentsmentioning

confidence: 99%

“…The changing temperature alters the mechanical properties during the forming process. Thus, as pointed out by preceding studies, thermal and mechanical analyses need to be fully coupled in the forming simulation of a thermoforming process [2,3].…”

Section: Introductionmentioning

confidence: 99%

A thermo-viscoelastic approach for the characterization and modeling of the bending behavior of thermoplastic composites

Ropers

Kardos

Osswald

2016

Composites Part A: Applied Science and Manufacturing

View full text Add to dashboard Cite

Please cite this article as: Ropers, S., Kardos, M., Osswald, T.A., A thermo-viscoelastic approach for the characterization and modeling of the bending behavior of thermoplastic composites, Composites: Part A (2016), doi: http://dx. AbstractCurrently, there is no established and cost-effective method for the bending characterization of continuous fiber reinforced thermoplastic composites. Isothermal mechanical testing techniques are time and labor-intensive and deliver information only about distinct points of the temperature-dependent property curves. In this study, Dynamic Mechanical Analysis (DMA) as well as novel rheometer-based bending experiments were performed to assess temperature-dependent and viscoelastic behavior. On the basis of the experimental results a new method was defined and validated for the efficient characterization of temperature-dependent elastic bending behavior via DMA. Furthermore a linear viscoelastic material model was derived from DMA experiments by means of time-temperature superposition. As the material behavior proved to be of a highly viscoelastic nature, a method was developed to calibrate a material model, the parallel rheological framework, implemented in Abaqus.

show abstract

“…While most of the effort is focused on developing constitutive models to represent the behaviour of the dry fabric during draping [3], it has been evidenced in recent studies that the forming cannot be considered adiabatic: when the laminate contacts the tool, its temperature rapidly decreases which can lead to local rigidification and formation of wrinkles. The thermomechanical models proposed thus far are either isothermal [4] or assume an homogeneous temperature field in the blank at the beginning of the forming step [5], which is complex to achieve in practice given the low conductivity of the polymers.…”

Section: Introductionmentioning

confidence: 99%

Towards a coupled heating-forming simulation of the thermoforming of thermoplastic composites

Baumard

Menary

Almeida

et al. 2017

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract.A strategy for the simulation of the whole thermoforming process, from the infrared heating to the stamping, is presented here. Two loosely coupled simulation tools are being developed: the first one computes a realistic 3D, transient temperature field of the composite stack inside an infrared oven, considering the radiative, conductive and convective heat transfers; the temperature distribution is used as an input for the second that aims at simulating the thermomechanical behaviour of the composite during the forming step via a non-orthogonal constitutive model. The steps for the identification of the model parameters are introduced. Initial validation tests show realistic results in term of shear angle distribution.

show abstract

Simulation of thermoplastic prepreg thermoforming based on a visco-hyperelastic model and a thermal homogenization

Cited by 114 publications

References 51 publications

Consolidation-Driven Defect Generation in Thick Composite Parts

Consolidation-Driven Defect Generation in Thick Composite Parts

A thermo-viscoelastic approach for the characterization and modeling of the bending behavior of thermoplastic composites

Towards a coupled heating-forming simulation of the thermoforming of thermoplastic composites

Contact Info

Product

Resources

About