Abstract
The linear thermal expansion coefficient of polycrystalline aluminum oxide has been measured in the temperature range from 100 °K to 1 500 °K by an interferometric method. The interferometer used is capable of giving high accuracy over a wide range of temperatures, and is described in some detail. The Grueneisen parameter of aluminum oxide is calculated and found to be 1.35 ± 0.05 over the whole temperature range. There is no significant change, such as might be expected from theory, of the Grueneisen parameter around 0.2 × Debye temperature. Based on the formulae given in an earlier publication, the temperature dependence of lattice vibration frequencies of aluminum oxide is calculated.