Heterogeneities Measurements of Crack Tip Deformation Fields in Random Short Spruce/PP Composites

Abstract

The random spruce short fiber reinforced polypropylene composites is a type of thermoplastic bio-composites. It is considered as homogeneous, isotropic in macro-scale of its specimen, in fiber scale about 500μm, the composite material appears heterogeneity, anisotropy due to the influence of microstructures of random short fibers. The heterogeneous deformations near the crack tip of the compact tension (CT) specimen which made from spruce/PP composites were measured by means of the digital image correlation method (DICM) with high resolutions digital image. The crack tip fields of heterogeneous displacement and strain for spruce/PP composites with fiber volume content 49% were obtained. The effects of random fiber microstructures on macroscopic deformations were discussed.