Ultrasonic Scattering in Two-Phase Polycrystalline Materials

Abstract

Many of the polycrystalline materials found in nature and those created using different manufacturing processes consist of multiple phases. Careful nondestructive characterization of these materials is of fundamental importance for quality assurance because microstructure is strongly correlated with mechanical performance. Ultrasonic scattering measurements have shown high sensitivity to material microstructure such that this approach is of interest for multi-phase materials. A fundamental understanding of scattering from idealized two-phase materials would provide essential information regarding the predictive nature of scattering measurements to quantify such microstructures. For this purpose, samples were created using spark plasma sintering (SPS) from mixtures with three different ratios (with respect to mass) of Cu and Fe powders. The three samples are • Cu-25 sample (mixture of 25% Cu & 75% Fe powder based on mass) • Cu-50 sample (mixture of 50% Cu & 50% Fe powder based on mass) • Cu-75 sample (mixture of 75% Cu & 25% Fe powder based on mass).