Cohesion:
Cohesion is a mass that resists separation. With epoxy repair materials; the resistance to the stress of expansion and contraction caused by wood's reaction to moisture. Brittle repair materials are subject to cracking or fracturing as wood moves. Resilient repair materials have good cohesive strength.
Epoxy repair materials with a high degree of Flexural Strength (ASTM D-790) resist cohesion failure.
Adhesion:
Bonding of two dissimilar materials. Quality of adhesion is affected by surface preparation, and the ability of epoxy material to penetrate the cellular structure of the wood fibers.
Ultra-low viscosity epoxy bonding agents with a high degree of Peel Strength (ASTM D-1876) resist adhesion failure.
Visit ASTM International for more information on flexural and peel strength: www.astm.org