Resonant Frequency Measurements for Powder Metallurgy Elastic Properties

Authors: C.J. Yu, R.J. Henry, T. Prucher, S. Parthasarathi, J. Jo of Concurrent Technologies Corporation

Abstract

The resonant frequency technique has proven to be a valuable tool for measuring, nondestructively, the elastic properties of powder metallurgy materials. This paper reports the results of a study on the use of resonant frequency techniques to determine elastic moduli of a wide range of pressed and sintered P/M materials. Resonant frequency techniques that were utilized included sine wave excitation, random signal excitation and impulse excitation. Results show good agreement between the elastic moduli determined dynamically and those obtained from mechanical testing (as published in MPIF Standard 35). The variation of elastic moduli with density is also presented. Also, an effort has been made to evaluate the accuracy of frequency measurements and the calculated elastic moduli for various testing techniques. These results suggest the use of nondestructive resonant frequency techniques as alternative tool to monitor elastic properties of P/M materials.