DISLOCATION DAMPING IN MAGNESIUM OXIDE CRYSTALS AT LOW FREQUENCIES
Abstract
Amplitude dependent internal friction measurements have been made on MgO crystals over the temperature range 0 to 300 C at frequencies of 5 cps. Analysis of the temperature dependency of the critical breakaway strain, delineating the transition from amplitude independent to amplitude dependent internal friction, permits an evaluation of the relative pinning strength of the Fe2+ and Fe3+ ions, less than .001 e and 0.035 eV respectively, determined on specimens from bulk sources. Optical absorption measurements confirm the presence of the Fe3+ ion in one bulk crystal and its absence in the other. (A UTHOR)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 26, 1962
- Accession Number
- AD0275064
Entities
People
- J.o. Brittain
- Philip Dahlberg
- R.d. Carnahan
Organizations
- Northwestern University