Bond strength is the amount of adhesion between bonded surfaces measured in terms of the stress required to separate a layer of material from the base to which it is bonded.
Bond strength generally involves determining the stress required to rupture a bond formed by an adhesive between two metal blocks. Often, the test involves the measurement of the shear and flexural bond strength of a bonding agent or a comparison of bonding agents under varying environmental conditions. The test may compare the fractured surface produced to failure analysis results within the adhesive inter-phase region.
The increased use of these adhesives in industry, especially in safety-critical areas, makes it necessary to evaluate any possible decrease in performance when subjected to impacts. Adhesive wedge peel test methods have been developed to evaluate fracture behavior of adhesively bonded joints when subjected to impact. The wedge-peel test is an ISO-standardized test method used to measure the resistance of structural adhesives to cleavage fracture at various speeds and user defined temperatures.
Orthodontics and medical adhesives are often tested using this method, although this general testing is used on a variety of products from paper to laminates to linoleum to construction adhesives. The test consists simply of a wedge, driven between two bonded surfaces under impact. Impact testing to this standard can deliver vital information to aid manufacturers in the research and development of new adhesives. Additionally, an environmental chamber enables the user to test at low and high temperatures, from -70 to -150°F.
• ASTM D903 - 98(2010) Standard Test Method for Peel or Stripping Strength of Adhesive Bonds
• ASTM C882 / C882M - 12 Standard Test Method for Bond Strength of Epoxy-Resin Systems Used With Concrete By Slant Shear
• ASTM F904 - 98(2008) Standard Test Method for Comparison of Bond Strength or Ply Adhesion of Similar Laminates Made from Flexible Materials
• ASTM D4796 - 10 Standard Test Method for Bond Strength of Thermoplastic Traffic Marking Materials