Accession Number : ADA184110

Title :   A Comparison of High Damping Shape Memory Alloys with Cu-Mn-Based and Fe-Cr-Based Alloys.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Cronauer,Joseph T

PDF Url : ADA184110

Report Date : Jun 1987

Pagination or Media Count : 104

Abstract : The strain dependence and temperature dependence of damping in the thermoelastic martensitic (shape memory) alloys titanium-nickel and copper zinc aluminum was compared to predetermined optimum damping behavior in the quiet alloys copper manganese aluminum and iron chromium molybdenum. Damping measurements were taken using a modified resonant dwell technique, in which cantilever beams were evaluated for damping at their first three resonant modes at temperatures between ambient and 110 C. Differential scanning calorimetry was used to correlate microstructural changes with damping capacity. All alloys that were conditioned for high damping showed a trend of low damping at low strains, a strain threshold, and increased damping with strains above the threshold. Damping was directly related to the progress of martensitic transformation in the titanium nickel alloy. The Copper, Zinc, Aluminum alloy was examined in a condition which did not develop high damping. Damping in the Iron, Chromium, Molybdenum, alloy was insensitive to temperature change.

Descriptors :   *ALLOYS, *DAMPING, *THERMOELASTICITY, CANTILEVER BEAMS, THESES, MEASUREMENT, RESONANCE, SENSITIVITY, TEMPERATURE, ALUMINUM ALLOYS, COPPER, ZINC, CAPACITY(QUANTITY), CALORIMETRY, SCANNING, COPPER ALLOYS, MANGANESE ALLOYS, PHASE TRANSFORMATIONS, THERMAL PROPERTIES, IRON ALLOYS, MOLYBDENUM ALLOYS, CHROMIUM ALLOYS, IRON, MARTENSITE, OPTIMIZATION, SHAPE, NICKEL ALLOYS, TITANIUM ALLOYS, MICROSTRUCTURE, MODIFICATION, RESONANCE

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE