An experimental assessment of hybrid bolted/bonded basalt fiber reinforced polymer composite joints' temperature-dependent mechanical performances by static and dynamic mechanical analyses

Bonded joint utilization is limited under elevated temperatures because of the polymer's relaxation. The hybrid bonded/bolted (HBB) joining allows more durable joints than both methods by combining the advantages of both techniques or minimizing their disadvantages. The present research systematically manifests the temperature's effect (under various isothermal conditions from room temperature to 150 °C) on the mechanical performances of bonded, bolted, and HBB composite single lap joints (SLJs). Tensile test results showed that the HBB joint's mechanical performance at room temperature (RT) increased by 47% and 89% relative to the bolted and bonded joints, respectively. Additionally, the jointed structures’ glass transition temperature (Tg) were evaluated by dynamic mechanical analysis (DMA). The bolted, bonded, and HBB joints’ Tg were obtained as 77.8, 107.9, and 111.2 °C, respectively. Besides, strong correlations were obtained between static tensile tests and DMA results, and a simplified model was developed to estimate the maximum tensile load values of single lab joints (SLJs).