Accession Number:

ADA361404

Title:

Round Robin Damping Testing on Nonlinear Material

Descriptive Note:

Technical rept.

Corporate Author:

NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD

Personal Author(s):

• Graesser, Edward J.
• Wong, Catherine R.
• Kinra, Vikram
• Friend, Danner
• Lavernia, Enrique

Report Date:

1998-12-01

Pagination or Media Count:

70.0

Abstract:

In order to assess the state of the art in damping measurements of metals, a round-robin series of damping tests was conducted. Two steels were employed in the work. One had high but nonlinear damping properties. The other was a high strength US Navy steel that had low damping properties. In this report, specimen damping test results are presented and compared. In addition, a procedure for converting from specimen damping to intrinsic damping is employed, and results are also presented on this basis. Furthermore, some test participants were able to measure the elastic modulus of the material while measuring damping, and this is also presented and discussed. It is clear from the work that large measured differences in both specimen and intrinsic damping can result when different test methods are employed. The differences are primarily attributed to systematic errors in certain testing procedures and sample design and size. In addition the method of loading and type of measurement may also account for some of the differences. A supported effort to establish a standard test sample and a standardized measurement approach is recommended to advance the state of the art in this field.

Descriptors:

• *DAMPING
• *ALLOYS
• STRESS STRAIN RELATIONS
• VIBRATION
• MODULUS OF ELASTICITY
• NONLINEAR SYSTEMS
• NOISE REDUCTION

Subject Categories:

• Properties of Metals and Alloys
• Acoustics
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE