Abstract
The adiabatic elastic constants of aluminum have been measured with an ultrasonic pulse technique at liquid-heluim, liquid-nitrogen, and room temperatures. The values of the elastic constants at 4°K are c11=11.63, c12=6.48, and c44=3.09 in units of 1010 N/m2. The Debye characteristic temperature calculated from these figures is θ=425°K in good agreement with the value obtained from speciffic heat data. The shear elastic constants ½(c11−c12) and c44 are discussed with reference to the theory given by Leigh.