Abstract
There are three Second Order Elastic Constants and six Third Order Elastic Constants for Al2O3 system. We calculate all the second and third Elastic Constants using Strain Elasticity theory. At standard temperature, the thermal properties of Al2O3 are theoretically analyzed. Grüneisen Parameters of the elastic waves at different angles of Al2O3 are evaluated using the elastic constants. The Brugger Gamma and normal-temperature Grüneisen Gamma are calculated by the method adopted by Menon and Ramji Rao. The volume expansion for Al2O3 system is positive since the normal-temperature value of Grüneisen Gamma is positive.