This part of ASTM D3163 specifies the test conditions for generating comparative shear strength data for joints made from a variety of plastics. This standard was designed to complement ASTM D1002 and to cover single-lap shear adhesive joints.
Many industries have moved toward adhesive bonding over traditional mechanical fasteners after stress cracking has become an issue. This standard provides a means for industries to evaluate the shear strengths of adhesive bonds and to compare various plastic surface treatments.
Lap-shear specimens are prepared in a manner which causes the test tabs to be in different planes. Grips that have adjustable clamping positions in the horizontal direction are recommended, as this will prevent the bonds from being damaged during clamping and will allow the direction of the tensile force to be in line with the bond. An alternate gripping technique would be to add spacers on each tab so that when the specimen is clamped, the mating surfaces of the two joints are vertical and positioned at the center of the load string. We recommend using advanced
screw-action grips and 5-10kN
pneumatic side acting grips for this application.