Tapered Double Cantilever Beam Fracture Tests of Phenolic-Wood Adhesive Joints


  • Robert Ebewele
  • Bryan River
  • James Koutsky


Tapered double cantilever beam, fracture energy, bondline thickness, grain angle, cure time, phenol-resorcinol


Tapered double cantilever beam specimens were developed and used to test the effects of bondline thickness, wood anisotropy, and cure time on the fracture energy of phenolic-wood adhesive joints. Fracture, energy, G10, increases slowly with bondline thickness (in the range 160-100 microns) then jumps considerably (100-90 microns), and finally drops sharply at bondline thicknesses less than 70 microns. As the grain orientation with respect to the bonded surface (grain angle) is increased from zero degrees, G10 decreases and goes through a minimum at about 20 degrees grain angle. At larger grain angles, G10 increases. The fracture energy also increases strongly with cure time, reaching a plateau at long cure times.


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