Abstract
It is shown that the elastic constants of metal plates can be measured by rotating plate technique in which the ultrasonic transmission is plotted as a function of the angle of incidence. As ultrasonic apparatus, a commercial "Roflectoscope" was used by which the defects of materials were tested with pulsed ultrasonics. The elastic constants of Al, Cu, Pb and Pb alloys have been measured with this equipment and the value obtained is shown to be in agreement with the value obtained by Marten's mirror method. It has been found that by this method the thickness of metal plates must be more than twice the wavelength of ultrasonics in the plates.
