METHOD FOR DETERMINING THE CRACK RESISTANCE INDICES OF COMPOSITE MATERIALS WITH TRANSVERSE REINFORCEMENT WITH A STITCHING THREAD Russian patent published in 2023 - IPC G01N3/08 

FIELD: testing techniques.

SUBSTANCE: invention relates to experimental methods for evaluating the properties of a polymer composite material (PCM) and can be used to determine the crack resistance of PCM reinforced with a stitching thread under loading mode I using standard samples in the form of a double cantilever beam (DCB). The method includes placing in the loading device a sample in the form of a double cantilever beam with an initial crack specified in the direction of the sample axis, exposing the sample in the area of the initial crack with a force through a loading device with a working element in the form of a rectangular metal plate with a thickness twice the thickness of the sample, the working surface of which has a descent at an angle equal to the opening angle of the crack, with a length of not more than 1/2 of the length of the original crack, with a rounded lower edge of the working surface, measuring the local length of the crack, from which the local interlayer fracture toughness is calculated.

EFFECT: improving the accuracy of determining the crack resistance indices of PCM with transverse reinforcement with a stitching thread and their determination by the location of the crack.

1 cl, 4 dwg