Properties of Cu-Al2O3 Nanocomposite Materials Synthesized by Mechano-Chemical Process

This study investigates the synthesis and characterization of Cu-(5 vol.%) Al2O3 nano-composites via a mechano-chemical process. CuO, Al, and Cu powders were mechanically alloyed for 12 h in an argon atmosphere, leading to the formation of Al2O3 nanoparticles within the Cu matrix. The composite powders were cold-compressed at pressures ranging from 200 to 400 MPa and sintered at temperatures between 700 °C and 900 °C for 1 to 3 h. X-ray diffraction and EDX analyses confirmed the disappearance of Al peaks, indicating the successful formation of Al2O3 in the Cu matrix. SEM images revealed Al2O3 particles (~10–20 nm) evenly distributed throughout the composite. The results demonstrated that increasing the compaction pressure from 200 MPa to 400 MPa reduced porosity by over 40%, enhancing microhardness by 30% and electrical conductivity by more than 32%, highlighting the significant influence of processing conditions, while lowering the effects in temperature and duration of sintering. These findings provide novel insights into optimizing Cu-Al2O3 composites via mechano-chemical routes.