Design and fabrication of an inverted torsion pendulum for internal friction measurements

We describe the design and construction of an inverted torsion pendulum for the measurement of the internal friction in high-damping solids in the frequency range 10 -3 -200 Hz and temperature range 4-600 K. The pendulum is attractive because of its simple construction and the use of many parts that are easily fabricated and/or readily available commercially. The sensitivity of the pendulum to internal friction as determined by tests on low-damping brass was found to be better than 0.5*10 -3 . We also present internal friction measurements on two metal dichalcogenides to demonstrate the versatility of the device.