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REFRACTORY INORGANIC NONMETALLIC MATERIALS, THEORY AND MECHANICAL PHENOMENA.
IIT RESEARCH INST CHICAGO ILL
Internal friction in plastically deformed silicon and indium antimonide single crystals is measured in the 400 cs to 80 kcs region, at temperatures up to 1200C. The internal friction vs. temperature curves are tentatively analyzed into two overlapping parts, a Bordoni peak and a high temperature rise. Measurements of the oxygen-relaxation peak in silicon, together with an assessment of oxygen concentration from measurements of the 9 micron infrared absorption line, have allowed the dipole strength of the interstitial oxygen defect to be derived. Further studies of anneal of a deformed magnesium oxide crystal containing about 0.05 chromium show that the activation energy of the anneal is very similar to that of purer crystals, about 2eV above 450C. The disorderedstrip model of dislocation damping is developed further, the theory put on a sounder basis, and the relative importance of thermodynamic and viscous damping assessed.
Rept. for 1 Apr 63-31 Mar 64