An evaluation of the curing characteristics of thermosetting epoxy carbon fiber sheet molding compounds and validation through computer simulations and molding trials

Abstract

Sheet molding compounds (SMC) are ready-to-mold thermoset composite materials reinforced with discontinuous fibers, usually compression molded.Finite element (FE) based compression molding tools can be employed to optimize this process; FE tools require to define material models using raw material data measured through different characterization techniques. In this study, the cure kinetics of an epoxy-based carbon fiber SMC has been characterized by means of differential scanning calorimetry (DSC) and moving die rheometer (MDR) techniques. Based on these datasets, Claxton-Liska and Kamal-Souror models have been set and the compression molding of a validation plate was performed, both experimentally and virtually. The results indicate that, even if both characterization techniques are valid for SMC curing characterization, MDR technique enables the characterization of the material at real molding temperatures and the model based on MDR leads to more accurate results.

Advancing on viscosity characterization and modeling of SMC for compression molding simulation

“…For this, in the ReactiveMold window within 3D TIMON CompositePRESS material modeling tool, the Arrhenius‐type Kamal model 37 (Equation ) needs to be calibrated. Cure kinetics of both materials were characterized following the methodology proposed by the authors in a previous publication 38 where refers to the curing rate, T the temperature and A 1 , A 2 , E 1 , and E 2 stand for material‐related coefficients.…”