Sol-gel techniques have been used to make mm-size pieces of Ni-alumina gels for abrasive use. The microstructure was studied extensively by electron microscopy methods and by electron and x-ray diffraction. The hardness, stiffness, and toughness were measured by indentation methods. Seeding of the gel with small additions of nm-size α-Al2O3 grains resulted in enhanced α-Al2O3 crystallization, a denser structure and better mechanical properties. The best Ni-alumina gel specimens had hardnesses and stiffnesses comparable to successful abrasive products and even better fracture toughnesses.
All Science Journal Classification (ASJC) codes
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering