Elastic Modulus by Resonance of Rectangular Prisms: Corrections for Edge Treatments

摘要

The dynamic elastic moduli of isotropic, homogeneous ceramics is commonly determined by resonance methods. A prismatic beam specimen is vibrated in a flexural mode, and the resonant frequency is measured. The beam may have a square, rectangular, or circular cross section. Elastic modulus is determined from the resonant frequency, the mass or density of the prism, and the beam's physical dimensions. Under ideal circumstances, the beam cross section should have a simple prismatic shape, but in practice, the method is sometimes applied to rectangular specimens with edge chamfers or radii that are applied to reduce edge flaw sensitivity during strength tests. The effect of such edge treatments on the resonance frequency and a simple means to correct the calculated elastic modulus for the edge treatment are provided in this note.