INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY, vol.120, no.5-6, pp.3731-3740, 2022 (SCI-Expanded)
In the present study, nickel matrix composites reinforced with in situ oxides were densified by the hot pressing process (HP). Mechanical alloying was used to synthesis in situ matrix and reinforced phases. The mechanical alloying process allows the ignition of aluminothermic reaction in the NiO/Al system. The formation of Ni-Al2O3 powder composites with residual NiO, indicating an incomplete reaction. At the end of the sintering process, two composites were formed: Ni-Al2O3 and Ni-NiAl2O4. The formed phases were identified by X-ray diffraction analysis (XRD) and examined by scanning electron microscopy (SEM). The density of composites was evaluated by the Archimedes method. The results revealed that the milling time significantly affected the density obtained after sintering. The highest density (5.74 g/cm(3)) was recorded for 10 h of milling. Composites' dry sliding wear behavior was tested using a ball-on-disc test under different loads. The tribological results show the impact of milling times and applied load on wear rate and the friction coefficient. The worn surfaces of the samples were examined by SEM to identify the wear behavior. Hence, abrasive wear was identified as the main mechanism.