强化聚合物的压缩测试的新方法
Ciprian Ionuț Morăraș1, Dorin Husaru2, Viorel Goanță1
1Mechanical Engineering, Mechatronics and Robotics Department, Mechanical Engineering Faculty, "Gheorghe Asachi" Technical University of Iasi, 700050 Iasi, Romania.
Polymers
|November 9, 2024
概括
玻璃纤维增强聚合物 (GFRP) 的压缩测试需要专门的方法来防止曲,并准确测量Poisson的比率. 一种使用T型红的新技术确定了这个比率为0.14,有限元素分析验证了实验结果.
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:
- 由于曲,薄复合板的压缩测试具有挑战性.
- 传统的光学方法,如数字图像相关性 (DIC) 和应变红,往往不适合这些测试.
- 准确确定像Poisson比率这样的材料属性对于复合材料应用至关重要.
研究的目的:
- 开发和验证一种可靠的方法,用于玻璃纤维增强聚合物 (GFRP) 样品的压力测试.
- 为了准确地确定GFRP的Poisson比率,使用一种新的样本设计.
- 通过有限元分析 (FEA) 研究力异常和制造缺陷对应力分布的影响.
主要方法:
- 使用ASTM D695 (波音版本) 和新提出的方法进行了压缩测试.
- 这种新方法使用了特殊的标本,使T型红能够粘合在一起,以测量Poisson的比率.
- 扫描电子显微镜 (SEM) 用于分析故障表面.
- 用有限元分析 (FEA) 来建模各种负载条件下的应力分布,包括偏心力和不对称的层厚度.
主要成果:
- 这种新方法成功地确定了GFRP的Poisson比率为0.14.
- 与对均载荷标本的实验数据相比,FEA结果显示出小误差 (应力为6.52%,应变为4.76%).
- 强力异常度显著影响了应力分布,导致最大应力大幅增加,最小应力大幅减少.
- 对不对称的外层树脂层的FEA分析强调了应力分布对制造缺陷的敏感性.
结论:
- 拟议的方法为GFRP的压缩测试提供了一个可行的替代方案,使得Poisson比率的准确确定成为可能.
- 压缩力的中心应用对于避免不均的应力分布和确保可靠的测试结果至关重要.
- FEA是了解应力度和压缩下复合材料缺陷影响的宝贵工具.
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