Role of Carbon‐Basalt Hybridization on the Impact Resistance and Damage Tolerance of Bonded Single Lap Joints

ABSTRACT In this study, the role of carbon‐basalt hybridization in improving the impact resistance and damage tolerance of bonded single lap joint has been evaluated. Therefore, four configurations of unidirectional plies stacked in cross ply sequence have been experimentally evaluated under low‐velocity impact and tensile‐after‐impact (TAI) loading. The configurations consist of two pure laminates (CCCC and BBBB) and two inter‐ply hybrids (CBBC and BCCB). Impact testing was performed using a drop‐weight apparatus, and residual strengths were measured through tensile testing on pre‐impacted samples. Results at 2.5 J impact show that (CCCC) laminates exhibit the highest peak impact forces, i.e., (1968.9 N) and residual strengths (3371.2 N), while (BBBB) and BCCB demonstrate lower stiffness but greater damage diffusion and energy absorption. The CBBC hybrid achieved the most effective balance, retaining tensile capacity close to (CCCC) joint configurations, (3360 N) at low energies and exhibiting enhanced impact resistance (2503.3 N, 27.14% increase), due to synergistic stress redistribution between carbon and basalt layers. SEM images further support these results by showing that the sandwiched basalt layers diffuse and spread damage, preventing cracks from directly reaching the adhesive layer, as occurs in (CCCC) joints, and thereby shifting the failure mode toward adhesive‐dominated behavior under tensile loading.