Ultrasonic Studies of Metallic Glasses
New results on ultrasonic properties of amorphous. PdSiCu are reported. The temperature and amplitude dependence of the ultrasonic attenuation and velocity changes were measured by a pulse echo method1), between 0.3 and 10 K, using transverse waves at 10 to 90 MHz and longitudinal waves at 30 MHz, A typical temperature dependence of the ultrasonic attenuation coefficient a for transverse waves at 25.1 MHz and four different amplitudes is shown in Fig. 1. As is seen from the figure, below 4 K there is a definite negative amplitude dependence. Detailed results of the amplitude dependent part αA at various temperatures are shown in Fig. 2. Measurements carried out at several different frequencies showed that αA increases as the ultrasonic frequency increases2). For longitudinal waves, there is a much smaller negative amplitude dependence of attenuation than for transverse waves.
KeywordsAttenuation Acoustics Verse
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- 1.The resolution of the equipment is better than 0.004 dB and 10−6 for amplitude and velocity change measurements, respectively.Google Scholar
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