Damage accumulation in braided textiles-reinforced composites under repeated impacts: Experimental and numerical studies

Abstract

Composites reinforced with braided textiles exhibit high structural stability and excellent damage tolerance, making them very attractive for defence, aerospace, automotive and energy industries. Considering the real-life service environment, it is crucial to study a dynamic response of a composite structure and its energy-dissipation ability, especially under repeated low-velocity impacts. So, a series of drop-weight tests were carried out followed by X-ray computed micro-tomography to characterize damage morphology of braided composite specimens. Meanwhile, a multi-scale computational approach was explored and implemented as a user-definedmaterial subroutine (VUMAT) for ABAQUS/Explicit to capture main damage modes of a braided textile composite, while its delamination was modelled by employing cohesive-zone elements. Load-and energy-time curves were obtained both experimentally and numerically. The predicted levels of peak forces and absorbed energy were found to agree with the experimental data. An extent of delamination and damage accumulation in the braided composite was predicted numerically and analysed; it was found that material responses to repeated impacts had two types depending on the level of normalised impact energy. The presented modelling capability could contribute to design of braided composite structures for various applications.

Residual Tensile Strength of the Multi-Impacted Scarf-Repaired Glass Fiber-Reinforced Polymer (GFRP) Composites

“…Multi-impact on composite laminates has been studied to understand progressive damage and damage strength degradation [21,22]. Many authors have studied the effect of multi-impact on external patch repair of the composite under specified conditions [11,22,23,24,25]. A few researchers have investigated the residual compressive strength of the repair-impacted composite [11,14,15,26].…”

Experimental and Numerical Study of the Influence of Pre-Existing Impact Damage on the Low-Velocity Impact Response of CFRP Panels

“…The Puck inter-fiber failure criterion has been accurately applied to CFRP [29,30], as in the work of [31], who developed a strain-based progressive damage model with IFF of Puck to simulate laminates subjected to low-velocity impacts. Progressive delamination in a woven composite subjected to repeated impacts was simulated in [32] using a cohesive zone model, showing that delamination propagates rapidly after the first impact.…”

Dynamic Response and Damage Accumulation of Laminated Composites under Repeated Low-Velocity Impacts

“…Experimental and numerical research has been conducted to study the repeated low-velocity impact responses of composites, which can be affected by many factors including impact energy, stacking sequence, specimen thickness, impactor shape, ambient temperature, etc. The dynamic responses of braided textile-reinforced composites under repeated low-velocity impacts studied by Wang et al [ 10 ] show two types according to the level of normalized impact energy. Under low-impact energy, the initial micro-cracks appear in the yarns first, causing the dominant failure mode of delamination with a low damage accumulation.…”