The Celanese compression test fixture GZ C-20 is suitable for the quasi-static characterisation of the compression properties of composites according to various standards. The test fixture is used for testing short, long and continuous fibre-reinforced plastics with thermoplastic or thermosetting base materials and is used for unidirectional layers or fabrics. In addition, isotropic materials such as pure resin or adhesive resin materials can also be tested with this test fixture.

The compression test fixture is required for testing fibre-reinforced plastics to prevent the specimen from buckling. With a specimen length of 110 mm, the free test length is only 10 mm. Strain gauges are applied to the centre of the specimen on both sides to determine the compressive strain and 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 specimen.