Assessment of the shear properties of thermoplastic composites using the ±45° tension and the V-notched rail shear methods

Abstract

Composite materials consisting of thermoplastic matrix are gaining the interest of both the aeronautical and the automotive industry as they comprise a series of advantages regarding their mechanical performance, their recyclability and their ability to be produced in large quantities. Nevertheless, some notable drawbacks have been noticed related to the fabrication process affecting their in-plane shear properties the characterization of which is complicated. Among the notable number of testing methods proposed throughout the years, several advantages and drawbacks were observed, mostly related to the way the load is applied, the stress uniformity and the applicability of each method to various material architectures. In the present work, the modified V-notched rail shear and the ±45° shear testing methods are applied to short and textile glass fiber reinforced thermoplastics aiming to assess the influence of both the fabrication method and the strands direction. Consecutively, the results obtained from the two different testing methods are compared revealing a relatively good agreement while, in parallel, the stress uniformity and the local failures observed on the specimens are analyzed.