The impact of boron nanoparticles on the shear performance and damage characteristics of dissimilar bonded joints

It is crucial for technological progress to research the addition of new nanoparticles to the adhesive compared to existing nanoparticles to increase the interface strength between the adhesive and the substrates and the durability of the adhesive joint in bonding processes. This study aims to experimentally investigate the effects of adding hexagonal nano-boron (nB) particles to the epoxy adhesive on the mechanical behavior of Al-GFRP single-lap joints (SLJ). Araldite 2014-2 was modified with nB particles at rates of 0.2%, 0.4%, 0.6%, and 0.8% by weight, and single-lap shear tests were conducted on the SLJ specimens. The maximum shear strength, 10.64 MPa, was recorded for the samples containing 0.4wt% nB particle. There was a 17.9% improvement in shear strength compared to samples without additives. In addition, the elongation at break in these samples increased by 37.6% compared to the pure sample, which shows that nB particles are effective in making the adhesive ductile. After the experiment, macro and scanning electron microscope (SEM) images of the damaged surfaces were examined. The inclusion of nB particles alters the bonding behavior from adhesive to cohesive. Additionally, damage mechanisms such as crack deflection, particle debonding, and subsequent plastic void growth have been observed in joints where nB particles were observed.