Shear Testing of Polymers

A shear test is a form of mechanical test that applies stress to a sample to determine the shear strength. This latter is the maximum stress that a material can undergo before that material fails. Shear testing of polymers such as adhesives is a common method to determine their shear strength. Shear testing involves applying parallel forces to the upper and lower faces of the object under test. When analysing polymers such as adhesives, the material is applied to two metal plates, each of which is dragged in the opposite direction to the other, until the two plates break apart completely. This stress is applied in a sliding motion. This is in contrast to tensile testing or compression testing, in which stress is applied in a perpendicular fashion. Shear testing to test sheer strength is important for product suitability for purpose and quality control, and can be used to measure the deformable strength of plastics, composites, fluids and other types of sample.