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Nonlinear Mechanical Property of 3D Braided Composites with Multi-Types Micro-Distortion: A Quantitative Evaluation
Junjun Zhai1,2,3, Xiangxia Kong3,4, Luchen Wang1,3
1College of Aeronautics and Astronautics, North China Institute of Aerospace Engineering, Langfang 065000, China.
Polymers
|March 29, 2023
Summary
A new method quantifies how yarn distortions affect 3D braided composite mechanical properties. Even minor distortions significantly impact performance, guiding composite design and optimization.
Area of Science:
- Materials Science
- Mechanical Engineering
- Computational Modeling
Background:
- Three-dimensional (3D) braided composites are advanced materials with complex structures.
- Yarn distortion significantly influences their mechanical properties, but is hard to quantify experimentally.
- Accurate characterization is crucial for optimizing composite performance.
Purpose of the Study:
- To develop an alternative calculation procedure to quantify the effect of yarn distortion on 3D braided carbon/resin composites.
- To analyze the influence of various yarn distortion factors and geometric parameters on mechanical properties.
- To provide a tool for design and structural optimization of complex composites.
Main Methods:
- Described multi-type yarn distortion factors (path, cross-section shape, torsion) using stochastic theory.
- Employed multiphase finite element method for complex discretization challenges.
- Performed parametric studies on yarn distortion and braiding geometry.
Main Results:
- The procedure captures yarn path and cross-section distortions from material squeezing, overcoming experimental limitations.
- Small yarn distortions were found to significantly impact mechanical properties.
- Different braiding geometries exhibit varying sensitivity to yarn distortion factors.
Conclusions:
- The developed procedure accurately quantifies yarn distortion effects in 3D braided composites.
- It offers an efficient computational tool for design and optimization of heterogeneous, anisotropic, or complex-geometry materials.
- Findings aid in understanding and mitigating distortion-induced property variations.
Keywords:
3D braidingcarbon/resin compositesfinite element analysismechanical propertiesmicro-distortionMore Related Videos
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