A novel hybrid WAAM-FSP approach for fabrication of ceramic-reinforced aluminum matrix nanocomposites

Aluminum nanocomposites, known for their superior properties, have gained significant attention in modern industries. This research employed a hybrid of wire arc additive manufacturing (WAAM) and friction stir processing (FSP) to fabricate aluminum nanocomposites incorporating zirconia (ZrO 2 ) nanoparticles. Aluminum specimens were created with seven layers of WAAM, and a groove was machined into each sample, filled with zirconia nanoparticles. The groove was then sealed using pinless FSP and then subjected to FSP with a pin tool in 2, 3, and 4 passes. Control samples included a two-pass FSP sample and a raw WAAM sample. Microstructure was conducted using optical microscopy (OM), field-emission scanning electron microscopy (FE-SEM), and X-ray diffraction (XRD). Mechanical properties were evaluated through tensile and microhardness testing, tribological properties via the pin-on-disk test, and corrosion resistance using electrochemical polarization testing. Results revealed that in the four-pass FSP nanocomposite sample, the grain size diminished by 92.36 % to 3.4 µm, while the microhardness increased by 64 % to 95.32 HV. The yield and tensile strength rose to 305 ± 18 and 469 ± 24 MPa, respectively. The friction coefficient and wear rate decreased, while the wear mechanism shifted from a mixed adhesive-abrasive wear to predominantly abrasive wear. The corrosion rate decreased to 17.52 µm.y −1 . • This study employed an innovative method that combines WAAM and FSP. • Increasing FSP passes decreased ZrO 2 agglomerate and grain size. • The lowest grain size (3.4 µm) is reached with a 4-pass FSP nanocomposite. • Nanocomposites show higher strength and less elongation than the raw sample. • Grain size decreases by 90 %, and UTS rises by 67.5 % in the optimized nanocomposite.