Study of Ultrasonic Attenuation on Aging Precipitation in A Ti-6Al-4V Alloy
Ti-6Al-4V alloy with different matrices was investigated by means of ultrasonic attenuation measurements. Widmanstätten and equiaxed microstructures were obtaining by heat treating a Ti-6Al-4V alloy. These two microstructures were over-aged at 545°C at different aging times. In order to find out the factors affecting the variation in the ultrasonic attenuation, the heat treated samples were examined by optical microscopy (OM) and (SEM) scanning electron microscopy. Based on the theory of ultrasonic attenuation in a solid media, the mechanisms of ultrasonic attenuation in the Ti-6Al-4V alloy with different matrices were analyzed. It was found that in both cases with Widmanstätten and equiaxed microstructures, the ultrasonic attenuation increased with frequency. The total ultrasonic attenuation was mainly attributed to the scattering loss which included the stochastic and the Rayleigh scattering due to the interaction between the ultrasonic wave and the material microstructure.