STUDY OF MICROMECHANICAL PROPERTIES OF ADHESIVE-BONDED JOINTS.

Abstract

The basic purpose of this program was to demonstrate the feasibility and utility of making microstrain measurements to establish the mechanical properties of adhesives in metal-metal bonds. Loading modes were tension, compression and shear as a function of joint thickness and test temperature for selected adhesive systems. A high sensitivity capacitance-type extensometer was used to measure the deformation. The following accomplishments were achieved: (1) Tensile mechanical properties of epoxy adhesives in bulk form are different from the epoxy in a metal bonded joint. (2) The tensile modulus increases with: decreasing thickness, increasing strain rate, lower test temperature, higher modulus adherends. (3) The shear modulus increases with decreasing test temperature, increasing strain rate and is independent of thickness in the range of 0.004 to 0.040 inches. (4) The precision elastic limit and the viscoelastic behavior are affected by composition, test temperature and stress level. (5) Several systems showed 'work hardening.' These techniques and results have provided new insights into the deformation characteristics of epoxy adhesives in metal bonded joints. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1968
Accession Number
AD0673745

Entities

People

  • Edward J. Hughes
  • John L. Rutherford

Tags

DTIC Thesaurus Topics

  • Adhesives
  • Bonded Joints
  • Joints
  • Measurement
  • Mechanical Properties
  • Metal Metal Bonds
  • Shear Modulus
  • Strain Rate
  • Stresses
  • Tensile Modulus
  • Tensile Properties
  • Thickness

Fields of Study

  • Materials science

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Structural Health Monitoring of Composite Structures.
  • Surface Engineering/Surface Coating Technology.