The Effect of Self-Healing Agent Fraction on CFRP Mechanical Behavior: Statistical Analysis Approach

Abstract

The self-healing application in structural composites aims to recover component properties, control damage propagation, and increase component life. In this way, this study proposes to characterize and predict the inter-laminar shear behavior of polymer composites (5HS carbon/epoxy) with different fractions of self-healing agent. In addition, this work aims to measure the influence of self-healing content on the mechanical response. The ANOVA evidenced that the healing agent fraction influences on mechanical properties more than the internal dispersion for the same laminate before the healing cycle. Weibull distribution evidenced a linear decrease in shear stresses for higher EMAA (poly(ethylene-co-methacrylic acid)) content, regarding stiffness decrease as a response to ductile thermoplastic behavior. Ineffective healing effects were observed for the translaminar and intra-laminar damage, once most particles were concentrated in inter-laminar sections. However, the healing efficiency reached an average of 62% for shear stress and 106% for toughness behavior, provided by the closing shear cracks, i.e., up to 57% of reduced area related to the initial crack size. The predictive approach before and after healing action in the mechanical behavior provides the appropriate self-healing level to meet the specific project requirements, thus saving time and cost.