Effects of Additives on Microstructure and Properties of Alumina-Silicon Carbide Nanocomposites

• Published in: Journal of the American Ceramic Society Vol. 82; no. 12; pp. 3609 - 3612
• Main Authors: Jeong, Young-Keun, Nakahira, Atsushi, Niihara, Koichi
• Format: Journal Article
• Language: English
• Published: Westerville, Ohio American Ceramics Society 01.12.1999; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; Structural ceramics; Technical ceramics; Hot isostatic pressing; Mechanical properties; Dispersion reinforced material; Experimental study; Fabrication property relation; Composite material; Structural ceramic; Additive; Silicon Carbides; Yttrium Oxides; Sintering; Nanocomposite; Fabrication structure relation; Manufacturing; Microstructure; Alumina; Magnesium Oxides
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.1999.tb02286.x

Al2O3/5‐vol%‐SiC nanocomposites have been fabricated by using pressureless sintering with MgO and/or Y2O3 sintering aids and post‐hot isostatic pressing (HIPing), which circumvents the limitations of hot pressing. Al2O3/SiC nanocomposites that have been doped with 0.1 wt% MgO and 0.1 wt% MgO + 0.1 wt% Y2O3 show an increased sintering density and a homogeneous microstructure, as well as a high fracture strength (1 GPa) after HIPing. In contrast, using Y2O3 as a dopant has a negative impact on the microstructure and the fracture strength. The results suggest that MgO, as a sintering additive, has a key role in improving the densification and controlling the microstructure of Al2O3/SiC nanocomposites.