Accession Number : ADD018306

Title :   High Damping Composite Joint for Mechanical Vibration and Acoustic Energy Dissipation.

Descriptive Note : Patent, Filed 17 Oct 94, patented 12 Nov 96,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Crane, Roger M ; Loup, Douglas C ; Gillespie, John W , Jr ; Andersen, Stephen M ; Coppens, Daniel D

Report Date : 12 Nov 1996

Pagination or Media Count : 8

Abstract : A design for a high damping composite joint which dissipates vibrations through the use of air gaps and viscoelastic material minimizing the transfer of vibrations to the metallic coupling. Viscoelastic material is used with adhesive to provide for increased energy dissipation by the joint. As the load increases on the joint, the load transfers from adhesive to the viscoelastic. The viscoelastic begins to take the load of the joint at the point where the adhesive becomes plastic. Acoustic vibrations are then dissipated in the viscoelastic and are prevented from being transferred to the metallic coupling by air gaps provided in the joint. The amount of viscoelastic and adhesive used depends on the anticipated load. Finite element analysis is used to calculate optimal amounts of viscoelastic and adhesive.

Descriptors :   *MECHANICAL PROPERTIES, *VIBRATION, *COMPOSITE MATERIALS, *ACOUSTIC WAVES, *ENERGY, *DAMPING, *DISSIPATION, *JOINTS, *AIR GAPS, COUPLING(INTERACTION), METALS, LOAD DISTRIBUTION, MATERIALS, FINITE ELEMENT ANALYSIS, VISCOELASTICITY, ADHESIVES, PATENTS

Subject Categories : Adhesives, Seals and Binders
      Couplers, Fasteners, and Joints
      Laminates and Composite Materials
      Acoustics
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE