Composite News
New drum peel test fixture GZ D-25
A drum peel test fixture is used to determine the resistance of core composites to peeling loads acting perpendicular to the surface layer, in accordance with DIN 53295 or similar standards. This test fixture is suitable for core composites whose surface layer can be wound around the drum during the test. The part of the core composite that is not wound around the drum (the core and the second top layer) must be sufficiently rigid to resist bending. The drum peel test fixture can be used in all standard universal testing machines.
During the test, the outer layer of a core-composite test specimen with a constant radius is peeled away from the core and wound onto a cylindrical drum. The loads during peeling are measured and recorded from the start to the end of the peeling process. To do this, one end of the test specimen is secured to the drum, whilst the other end is clamped into the upper specimen holder mounted in the universal testing machine.
This means that specimens with a length of 110…160 mm and a width of 6…25 mm can be tested. According to the standards, the use of tabs is not mandatory, but recommended in order to avoid too large a stress step between the clamping area and the free test surface and consequently clamping fractures. Strain gauges are applied to the centre of the specimen on both sides in order to determine the compressive stiffness, the strain at failure and the buckling. The test fixture consists of clamping wedges which, according to the self-reinforcing principle, divert the axial force of the testing machine into a transverse force for clamping the test specimen.
