Acoustic quality factor of aluminum alloys from 50 mK to 300 K

Journal Article · Sat Dec 01 04:00:00 EST 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.346971· OSTI ID:6257223

Duffy, W Jr ^[1]

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1. Department of Physics, Santa Clara University, Santa Clara, CA 95053 (USA)

Measurements of the acoustic quality factor (reciprocal internal friction) of commercial aluminum alloys 2090, 5056, and 6061 in a torsional vibrational mode at a frequency of 1 kHz in the temperature range from 50 mK to 300 K are reported. The temperature dependence of the mode frequency, which is a measure of the shear modulus of the material, is also given. The quality factor ({ital Q}) of all alloys exhibited the highest values at the lowest measurement temperature. A heat-treated sample of the 5056 alloy gave the highest {ital Q} of 6.5{times}10{sup 7} at 53 mK. Maximum {ital Q} values of 8.9{times}10{sup 6} in 2090 and 6.5{times}10{sup 6} in 6061 were observed. Internal friction mechanisms which may explain the measured {ital Q} values are discussed. The results provide support for the planned construction and operation of very sensitive 50-mK aluminum-alloy bar gravity-wave detectors.

• OSTI ID: 6257223
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 68:11; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104 -- Metals & Alloys-- Physical Properties
640106* -- Astrophysics & Cosmology-- Cosmology
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACOUSTICS
ALLOYS
ALUMINIUM ALLOYS
ELECTRONIC EQUIPMENT
ENERGY LEVELS
EQUIPMENT
EXCITED STATES
FRICTION
GRAVITATIONAL WAVE DETECTORS
INTERNAL FRICTION
LOW TEMPERATURE
MEASURING INSTRUMENTS
MEDIUM TEMPERATURE
RADIATION DETECTORS
RESONATORS
SENSITIVITY
SIGNAL-TO-NOISE RATIO
TEMPERATURE DEPENDENCE
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE
VIBRATIONAL STATES