Preparative procedures, densification, grain growth and change in corundum lattice dimensions in sintered compacts made from chromium(III)oxide/aluminium(III) oxide mixtures were evaluated in a study of alumina-chrome refractories. High energy milling using A-17 "reactive" alumina gave densification at low temperature and the most rapid grain growth, also (by Weibull analysis) the least variability in modulus of rupture, 7% W/W chromium(III)oxide giving minimum strength. XRD confirmed solid solution formation, the corundum lattice dimensions contracting with 7% W/W chromium(III)oxide, other compositions giving lattice expansion. The modulus of rupture at 1150°C for a series of ethylsilicate-bonded alumina refractories containing 5-12% W/W chromium(III)oxide and fired at 1700°C was also a minimum at 7% W/W chromium(III)oxide.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry