Resonant Ultrasound Spectroscopy (RUS) for Determining Elastic Moduli of Soft Materials

The elastic moduli give important information needed for engineering applications. Simple techniques for finding them can greatly aid in developing designs by understanding material properties. Based on the classical RUS design [1] we have built an instrument for exploring materials elasticity. In our setup the excitation signal is driven with a Rohde & Schwarz signal generator (SMY-01) connected to a piezoelectric transducer. Having passed through the sample, the signal is received by another transducer and cleaned up with a Stanford Research Systems (SR810-DSP) lock-in amplifier. The advantage of our setup is that it allows for work at low frequencies, which implies possibility of studying soft materials. Performance of the instrument was tested on recording the resonances of aluminum and magnesium samples with the purpose of elucidating their elastic moduli. Another benefit of our design is that it does not require expensive components and can be adopted for undergraduate education.<br/>[1] A. Migliori, J. Sarrao, “Resonant Ultrasound Spectroscopy”, 202 p., Wiley-VCH, 1997<br/>This work was partially supported by NSF CMMI # 1934370