Low-Temperature Elastic Moduli of Aluminum

The adiabatic elastic moduli of single crystals of aluminum have been measured from 4.2° to 300°K by using the ultrasonic pulse-echo technique. The values obtained by extrapolation to 0°K are C11=11.430, C12=6.192, and C44=3.162 in units of 1011 dyn/cm2. The Debye temperature obtained from the 0°K modulus values is 430.3°K, in excellent agreement with the value from heat-capacity measurements.