Boundary Layer Thermal Stresses in Angle-Ply Composite Laminates. Part 1.

Abstract

Thermal boundary-layer stresses (near free edges) and displacements are determined by a unique method developed under this grant. This method consists of an eigenfunction expansion technique and the establishment of an appropriate particular solution. Current solutions in the region away from the singular domain (free edge) are found to be excellent agreement with existing approximate numerical results. As the edge is approached, the singular term controls the near field behavior of the boundary layer. Results are presented for cases of various angle-ply graphite/epoxy laminates with (e/-e/-e/9) configurations rough-the-thickness) stresses. Thermal boundary-layer thicknesses of different composite systems are determined by examining the strain energy density distribution in composites. It is shown that the boundary-layer thickness depends on the degree of anisotropy of each individual lamina, thermomechanical properties of each ply, and the relative thickness of adjacent layers. Also, the interlaminar thermal stresses are compressive with increasing temperature. The corresponding residual stresses are tensile and may enhance interply delaminations. (MM)

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1981
Accession Number
ADA302712

Entities

People

  • I. Choi
  • S. S. Wang

Organizations

  • University of Illinois Urbana–Champaign

Tags

Communities of Interest

  • Air Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Composite Materials
  • Differential Equations
  • Epoxy Composites
  • Epoxy Laminates
  • Failure Mode And Effect Analysis
  • Far Field
  • Finite Element Analysis
  • Geometry
  • Graphite Epoxy Composites
  • Jet Propulsion
  • Laminates
  • Materials
  • Materials Laboratories
  • Mechanics
  • Navy
  • Partial Differential Equations

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Structural Health Monitoring of Composite Structures.