Damage evolution in low velocity impacted unreinforced vinyl ester 411‐350 and 411‐C50 resin systems

Abstract

Damage evolution in plaques made of vinyl ester resin systems was investigated as a function of specimen thickness, impact energy level and matrix material. Dow DERAKANE vinyl ester 41 1-350 and 41 1-C50 resin systems, which have low viscosity and are ideally suited for low-cost liquid processing techniques like vacuum assisted resin transfer molding (VAIITM). were considered for the low velocity instrumented impact testing. Characterization of damage evolution was undertaken using optical microscopy and analysis of impact load histories recorded during the impact event. Radial cracking, perforations at the point of impact [in the form of a truncated cone), and damage resulting from the support constraints were identified as the dominant failure characteristics in both resin systems. Radial cracking, which originated from the bottom surface, was operative in all failed specimens and was attributed to the catastrophic failure due to extensive flexural tensile strength losses. For specimens that could deflect significantly, radial cracking and supportconstraint-induced damage were the operative failure mechanisms. Radial cracking and through-thickness shearing led to failure in stiffer plaques. The DERAKANE 4 1 1 -350-vinyl ester resin system was found more damage resistant than the 4 1 14250 system.

Parametric studies on self-repairing approaches for resin infused composites subjected to low velocity impact

“…Time-to-maximum load decreased linearly and the ratio of total energy-to-impact energy (E t /E m ) remained constant with impact energy level. The results and general trends of VE C50 impact parameters with impact energy are in agreement with previously published results for unreinforced or neat resin plaques [47][48][49]. For EPON-862 laminates, maximum load and energy-to-maximum load decreased parabolically, whereas deflection-at-maximum load increased in a parabolic manner with impact energy.…”

“…The results of neat resin plaques and neat resin with ply are minimally mentioned in this manuscript. Details of the impact response and damage evolution in neat resin plaques and neat resin with ply were presented previously [47][48][49].…”

Self healing in polymers and polymer composites. Concepts, realization and outlook: A review

“…Complete filling of healing agent into the tiny tubes was achieved by vacuum assisted capillary action filling technique. Accordingly, three types of healing system were developed ( Figure 2) [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. (i) Single-part adhesive.…”

“…With the aid of the pre-embedded healing system in hollow pipettes, Motuku and co-workers studied the healing ability of glass fiber/unsaturated polyester composites subjected to low velocity impact [36,43]. The species of healing agent, characteristic parameters of the hollow pipes (amount, type of tubing materials and spatial distribution), composites panel thickness, and impact energy level were found to be critical to the healing efficiency.…”