Extended capabilities of a vibrating-reed internal friction apparatus

Two developments are described in a vibrating-reed technique used for internal friction studies of foils and thin films. One is an activation procedure that enables measurements to be made on the blank reeds of fused silica used as substrates for thin films. This procedure is also relevant to the study of insulating films. The other development is an ability to make measurements on electrically conducting samples in both torsional and flexural vibration.