Effect of aluminum oxide nanoparticles on friction stir welding of acrylonitrile butadiene styrene sheet joints

Friction stir welding (FSW) is an important technology for welding thermoplastics. In this study, acrylonitrile butadiene styrene (ABS) sheets were joined by FSW and aluminum oxide nanoparticles (1, 3 and 5 vol%) were added to the joints by friction stir processing (FSP). The aim was to evaluate the potential of Al 2 O 3 nanoparticles as an inexpensive reinforcement for ABS joints. Results showed Al 2 O 3 nanoparticle improves tensile strength, flexural strength, thermal degradation temperature and wear resistance while it decreases impact energy. Highest tensile strength (36.5 ± 0.78 MPa) and flexural strength (58.78 ± 0.40 MPa) were achieved with 3 vol% and 5 vol% Al 2 O 3 nanoparticles, respectively. Also, highest degradation temperatures corresponding to 10 wt% and 50 wt% weight loss (404.5 ± 0.5 °C and 446.5 ± 0.5 °C, respectively) and lowest coefficient of friction (0.380 ± 0.003) were achieved with 5 vol% Al 2 O 3 nanoparticles. Furthermore, two- and four-stage welding were applied to samples with 3 vol% Al 2 O 3 joints. Two-stage welding increased tensile and flexural strength to 38.92 ± 0.68 and 76.03 ± 2.29 MPa, respectively, however, four-stage welding decreased both tensile and flexural strength. Scanning electron microscope images confirmed two-stage welding improves the dispersion of aluminum oxide nanoparticles while four-stage welding introduced considerable number of voids. Therefore, this study suggests aluminum oxide nanoparticle as an effective inexpensive reinforcement to improve tensile, flexural, wear resistance and thermal stability of friction stir welded ABS sheets.