DISLOCATION DAMPING DUE TO EXTENDED DISLOCATIONS

Dislocation damping measurements have been made on a series of Fe-18Cr-Ni alloys ranging from 10 to 20 wt. % Ni in an effort to relate damping behavior to stacking fault width. Data have been obtained on 〈110〉 single crystals, both with the resonance bar technique at 80 KHz, and the pulse attenuation technique at 15 to 105 MHz. The results indicate that amplitude-independent and amplitude-dependent damping decrease as Ni content increases. The data can be interpreted qualitatively in terms of the vibrating string model and the Granato-Lücke damping theory. The composition difference between bulk phase and stacking fault appears to influence the damping behavior more strongly than the width of the fault per se. These results are discussed in terms of an extension of the theory of solute segregation to stacking faults. © 1969.