Thermal expansion of solids at high temperatures by the gamma attenuation technique

A new technique is described for the measurement of the thermal expansion of isotropic solid materials at high temperatures. The method utilizes gamma attenuation to measure thermal expansion with a noncontacting probe. The experimental apparatus and analytical method are described, and results are presented for aluminum to 900 K and type 303 stainless steel to 1660 K to illustrate the use and precision of the technique. These results agree with published values measured by other techniques, and in the case of the stainless steel alloy, some new results are presented in the temperature range 1400-1660 K.