Micromechanical Modelling of Dynamic Behavior of Advanced Sheet Molding Compound (A-SMC) Composite

Abstract

Passive safety, particularly in the transport industry, requires maximizing the dissipation of energy and minimizing the decelerations undergone by a vehicle following a violent impact (crash). This paper proposes a strategy for identifying an anisotropic local damage criterion in a moderate dynamic loading for Advanced Sheet Molding Compound (A-SMC) composite materials. Multi-scale damage modelling based on the Mori-Tanaka approach is put forward. Previously, the results of an experimental campaign carried out on a range of strain rates varying from quasi static to 200 s −1 were used to identify a probabilistic local damage criterion based on Weibull's formulation and integrate the effect of damage at a fiber-matrix interface scale. Therefore, the progressive local damage occurring under a fast loading may be described. A two-step homogenization procedure allows describing the strain rate effect on the stress-strain curves. The model gives also rise to the prediction of the progressive anisotropic loss of stiffness. Comparing between the experimental and numerical results confirms the ability of the proposed approach to describe the visco-damage effect (delay of damage threshold and decrease in damage kinetics) emphasized in A-SMC composites.

Multi‐scale analysis of short glass fiber‐reinforced polypropylene under monotonic and fatigue loading

“…The last stage is characterized by a drastic decline in stiffness due to rapid crack propagation leading to failure. The Analysis of the stiffness reduction during loading‐unloading monotonic tests is used by several authors [ 7–9 ] to evaluate the macroscopic damage evolutions of SFRC. During the fatigue test, the dynamic modulus (slope of the stress‐strain hysteresis) is commonly used as a damage indicator.…”

Monitoring damage evolution with acoustic emission in two types of glass epoxy laminates

“…[1][2][3][4][5] However, during their use, composite materials may suffer from a wide variety of damage: defects due to exposure to humidity, temperature cycling, mechanical fatigue or impact. [6][7][8][9][10] To quantify and identify this damage, the application of non-destructive testing (NDT) is necessary. Assessing the degree of damage in composite materials is a major industrial issue.…”