Abstract
Ultrasonic propagation velocities of both longitudinal and shear waves through thermoplastic resin discs of polymethyl methacrylate, polystyrene, and polyvinyl chloride were measured. The results obtained were compared with those of an immersion sing-around method, changing the incidence angle from water to the specimen, and the ultrasonic pulse echo method. For both cases, the carrier frequency used is 2 MHz. The density was measured by a hydrostatic weighing method. Longitudinal modulus, shear modulus, Young's modulus, bulk modulus, Poisson's ratio, and microhardness were calculated and tabulated. The ultrasonic attenuation and ultrasonic viscosity of the studded materials were determined.