Comparisons of tension–tension fatigue behavior between the 3D orthogonal woven and biaxial warp-knitted composites

Abstract

In this article, the tensile fatigue properties of 3D orthogonal woven composites (3DOWCs) and biaxial warp knitted composites in 0°, 30°, 45°and 90° directions were studied and compared experimentally. The quasi-static tensile test and tension–tension fatigue test were carried out to obtain the stress–strain curves, the S–N curves and stiffness degradation curves. The results indicate that the two types of composites both exhibit greater stress in 0° and 90° directions and greater strain in 30° and 45° directions. The S–N curves obtained by experimental fitting can better reflect the fatigue degree of the two composites. The stiffness degradation rate of 3DOWCs is much higher than that of biaxial warp-knitted composites except in the 90° direction. The aim of this study is to provide a theoretical study for two kinds of composites to ensure the longest service life in practical applications.

Keywords:

• 3D orthogonal woven composites (3DOWCs)
• biaxial warp-knitted composites (BWKCs)
• quasi-static tensile
• tension–tension fatigue
• stiffness degradation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Open Project Program of Key Laboratory of Yarn Materials Forming and Composite Processing Technology of Zhejiang Province (No. MTC2019-09), the National Natural Science Foundation of China (No. 51765051, No. 51805210), the Natural Science Foundation of Inner Mongolia (No. 2017MS0102, No. 2018MS05055) and Jiaxing Program of Science and Technology (Grant No.2019AD32005).