GB/T 45471-2025Test method for mode III interlaminar fracture toughness of carbon fiber reinforced composite materials — Edge crack torsion method (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting.

Please note that some of the contents of this document may involve patents. The issuing organization of this document does not assume the responsibility for identifying patents.

This document is proposed and coordinated by the National Carbon Fiber Standardization Technical Committee (SAC/TC572).

This document was drafted by: China Aircraft Strength Research Institute, Nanjing Fiberglass Research and Design Institute Co., Ltd., China Aviation Manufacturing Technology Research Institute Research Institute, Shenyang Aircraft Design and Research Institute of Aviation Industry Corporation of China, and Shanghai Qinyao Aviation Testing Technology Co., Ltd.

The main drafters of this document are: Song Guibin, Li Lei, Wang Binwen, Duan Minge, Li Xiaolong, Xie Jiahui, Xiong Huafeng, Sui Xiaodong, Shi Fenghui, Ma Dan, Chen Xiangming, Si Kui, Tang Kun, and Song Nan.

Mode III interlaminar fracture toughness of carbon fiber reinforced composites Determination of edge crack torsion method

1 Scope

This document describes the principle, test equipment, test specimens, test methods and test methods of carbon fiber reinforced composite material type III interlaminar fracture toughness test method.

The test conditions and test steps are given, as well as the calculation formula and the writing content of the test report.

This document is applicable to the determination of mode III interlaminar fracture toughness of carbon fiber reinforced composite laminates.

2 Normative references

GB/T 1446

GB/T 3961

GB/T 40724

3 Terms and definitions

The terms and definitions defined in GB/T 3961 and GB/T 40724 and the following apply to this document.

4 Principle

The load is applied to the edge-cut specimen in the form of torsion loading (see Figure 1), so that the specimen is subjected to the tauZX shear stress (X direction on the ZX plane).

The delamination expansion occurs under the action of shear stress, thereby obtaining the mode III interlaminar fracture toughness (GIIIC) of carbon fiber reinforced composite materials.