通过引入最佳配置文件,通过全球补偿方法提高CFRP的形成精度
Yongming Zhang1, Luling An1, Cong Zhao1
1Collage of Mechanical & Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Polymers
|July 13, 2024
概括
在复合结构中最大限度地减少固化扭曲至关重要. 这项研究引入了最佳补偿配置方法,在复合墙面板中显著减少了86.2%的扭曲.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 复合材料 复合材料 复合材料
背景情况:
- 不可逆转的固化扭曲限制了高性能复合结构应用.
- 固化扭曲被定义为在拆模后偏离理论形状的偏差.
- 提高碳纤维增强聚合物 (CFRP) 的成型精度需要解决这种扭曲.
研究的目的:
- 建立一个协调的控制模型,以优化CFRP固化中的补偿配置.
- 调查加热,保持和冷却时间对固化扭曲和残余应力的影响.
- 验证一个多场合的有限元模型,用于预测和最小化固化扭曲.
主要方法:
- 开发一个协调的控制模型,包含四个扭曲参数 (D_av,D_msr,D_min,D_max).
- 使用全球补偿方法制造两种尺寸的复合结构部件.
- 创建和验证一个多领域合的有限元模型来模拟固化过程.
主要成果:
- 有限元模型与实验发现有很强的一致性.
- 增加加热和保持时间减少了中间层的残余应力,而增加冷却时间则产生了相反的效果.
- 精炼固化过程参数将指定树脂系统内的固化变形降至最低.
结论:
- 全球补偿方法有效地减少了复合结构中的固化扭曲.
- 开发的数值模型准确地预测了固化扭曲和残余应力.
- 优化固化过程参数是实现高精度复合材料组件的关键.
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