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This study investigates the high-velocity impact mechanics in correlation with piezo-resistance damage sensing characteristics of glass/carbon hybrid composites under projectile impact loading. Inter-ply and Intra-ply hybrid composites consisting of different ply orientations, stacking sequences, and liquid metal (LM) compositions (1 and 2 wt%) are considered for this study. An in-house one-stage gas gun setup is used to conduct projectile impact loading experiments. A novel circumferential four probes electrical resistivity method is employed to investigate the damage-sensing capability of hybrid composites. Two different projectile shapes (cone end projectile and stepped cone end projectile) are considered and investigated their effect on the composites’ ballistic limit, impact energy absorption, damage area, and piezo-resistance response. Projectile shape significantly influences ballistic limit and energy absorption, whereas a stepped cone end projectile demonstrates higher amount of energy absorption of about 42% and peak piezo-resistance change of around 60% compared to cone end projectile. The addition of LM improved the ballistic limit by about 20% and the amount of energy absorption by around 50% but reduced damage-sensing sensitivity due to improved electrical conductivity with its presence. Moreover, the intra-ply hybrid composites exhibited lower ballistic limits owing to weaker fiber strength, while inter-ply hybrids showed better energy absorption capabilities, resulting in higher ballistic limits. Thermal imaging technique is adopted in post-mortem analysis of the damaged area, and it revealed delamination inside the intra-ply hybrid composites. 

Abstract Short oligomeric peptides typically do not exhibit the entanglements required for the formation of nanofibers via electrospinning. In this study, the synthesis of nanofibers composed of tyrosine‐based dipeptides via electrospinning, has been demonstrated. The morphology, mechanical stiffness, biocompatibility, and stability under physiological conditions of such biodegradable nanofibers were characterized. The electrospun peptide nanofibers have diameters less than 100 nm and high mechanical stiffness. Raman and infrared signatures of the peptide nanofibers indicate that the electrostatic forces and solvents used in the electrospinning process lead to secondary structures different from self‐assembled nanostructures composed of similar peptides. Crosslinking of the dipeptide nanofibers using 1,6‐diisohexanecyanate (HMDI) improved the physiological stability, and initial biocompatibility testing with human and rat neural cell lines indicate no cytotoxicity. Such electrospun peptides open up a realm of biomaterials design with specific biochemical compositions for potential biomedical applications such as tissue repair, drug delivery, and coatings for implants.