한국주조공학회

Mechanical properties of (10%Al₂O₃∙SiO₂+5%Ni)/Al hybrid composites fabricated by the reaction squeeze casting were compared with those of (15%Al₂O₃∙SiO₂)/Ai composites. Al-Ni intermetallic compounds (10~20μм) formed by the reaction between nickel powder and molten aluminum were uniformly distributed in the Al matrix. These intermetallic compounds were identified as Al₃Ni using X-ray diffraction analysis and they resulted in beneficial effects on room and high temperature strength and wear resistance. Microhardness values of (10%Al₂O₃∙SiO₂+5%Ni)/Al hybrid composite were greater by about 100Hv than those of (15%Al₂O₃∙SiO₂)/Al composite. Wear resistance of (10%Al₂O₃∙SiO₂+5%Ni)/Al hybrid composites was superior to that of (15%Al₂O₃∙SiO₂)/Al composites regardless of the applied load. While tensile and yield strength of (10%Al₂O₃∙SiO₂+5%Ni)/Al hybrid composites were greater at room temperature and 300℃, strength drop at high temperature was much smaller in hybrid composites.