Determination of dynamic properties or sintered copper powder from ultrasonic measurements

The overall (effective) dynamic properties of sintered copper powder with air-saturated pores at moderate porosities are deduced from suitable ultrasonic measurements carried out at low porosities in the long-wavelength approximation. The effective dynamic properties of the two-phase composite at low and moderate porosities are analysed computationally, the properties of the pure matrix material being in the first step determined by extrapolation from suitable ultrasonic measurements carried out at low porosities, and by employing the Berryman's self-consistent single scattering theory. The presented results confirm the ultrasonic measurements to be extremely useful in estimating the influence of the volume concentration and shape of the inclusions on the overall dynamic properties of porous two-phase composites at porosities from a wide range of porosity. Keywords: ultrasonics, porous composite, inclusion shape.