Damping Ratio Measurements In Kevlar Sandwich Samples
Report Number: WL-TR-91-3078 Volume III, p. IBD-1
Author(s): Balis-Crema, L., Agneni, A., Castellani, A.
Corporate Author(s): University of Rome
Date of Publication: 1991
Pages: 1
DoD Task:
Identifier: This paper is part of a conference proceedings. See ADA241313
Abstract:
Unlike some structural aerospace materials, as for instance carbon fibers, Kevlar composites present high damping ratios. This characteristic seems important in the structural design of satellites and large spacecraft. Besides the use of Kevlar sandwich structures is particularly interesting because of their high specific stiffness. This paper presents the experimental results of damping ratio measurements derived from several sandwich samples, characterized by different skins, fabric and laminate with different lay-up. Damping ratios are evaluated by using different techniques and a comparison is discussed. The effects of frequency and temperature - in the range from the room value up to 100 Centigrade - on the damping ratio values are also considered. A model (based on an energetic approach), that permits a theoretical estimate of the damping ratio in sandwich samples is presented. Finally a comparison between the experimental and the predicted values is carried out. FULL PAPER NOT AVAILABLE FOR PUBLICATION
Author(s): Balis-Crema, L., Agneni, A., Castellani, A.
Corporate Author(s): University of Rome
Date of Publication: 1991
Pages: 1
DoD Task:
Identifier: This paper is part of a conference proceedings. See ADA241313
Abstract:
Unlike some structural aerospace materials, as for instance carbon fibers, Kevlar composites present high damping ratios. This characteristic seems important in the structural design of satellites and large spacecraft. Besides the use of Kevlar sandwich structures is particularly interesting because of their high specific stiffness. This paper presents the experimental results of damping ratio measurements derived from several sandwich samples, characterized by different skins, fabric and laminate with different lay-up. Damping ratios are evaluated by using different techniques and a comparison is discussed. The effects of frequency and temperature - in the range from the room value up to 100 Centigrade - on the damping ratio values are also considered. A model (based on an energetic approach), that permits a theoretical estimate of the damping ratio in sandwich samples is presented. Finally a comparison between the experimental and the predicted values is carried out. FULL PAPER NOT AVAILABLE FOR PUBLICATION
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This report is part of the following conference:
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Proceedings of Damping '91: 13-15 February 1991 San Diego, California (GCA-1 through JCB-17)
WL-TR-91-3078 Volume III