Evaluation of Dislocation Pinning Effects from Simultaneous Measurements of Attenuation and Sound Velocity in Copper
نویسندگان
چکیده
The frequency dependence00 to 200 M H Z ~ O ~ the sound velocity and of the ultrasonic attenuation a has been measured on high purity Cu during 3 MeV y-irradiation at room temperature. The results are evaluated with respect to dislocation effects which under the present conditions cause the major contributions to the frequency dependent reduction of sound velocity AvD!v0 and attenuation aD. The y-dose dependence of AvD/v0 and a~ is In complete accordance with the Granato-Lucke theory of dislocation resonance damping. It is shown that simultaneous measurements of AvD/vo and aD strongly improve the accuracy of MHz-investigations of dislocation damping effects.
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