No abstract

The methodology to extract in-plane shear properties have been standardised for polymer-based composite materials. However, no standards have been designed to extract reliable test data for nonfibre reinforced polymers, which can be used to calibrate finite element material models. The quality of the results from three widely used experimental techniques was examined in this study for mineralfilled polypropylene in terms of shear strain distribution, out-of-plane deformations and shear stressstrain curves with the aid of digital image correlation method. The V-Notched Rail test (ASTM D7078) exhibited ultimate fracture of the specimen, but valid shear strain was only obtained for small deformations. For relatively large strains, more reliable shear test data were found for a modified version of ASTM B831: a standard test designed for aluminium but modified for polymers. Although out-of-plane deformations were avoided using aluminium holders, large variability was found in the strain distribution along the shear path. In contrast, the modified Wyoming Iosipescu test (ASTM D5379) exhibited the most robust shear stress-strain results due to consistent shear strain uniformity and low variability during the entire duration of the test.