使用工艺和有限元模拟研究PBAT聚合物的辅助结构变形行为
Yanling Schneider1, Vinzenz Guski1, Ahmet O Sahin1
1Institute for Materials Testing, Materials Science and Strength of Materials (IMWF), University of Stuttgart, Pfaffenwaldring 32, D-70569 Stuttgart, Germany.
Polymers
|July 29, 2023
概括
这项研究探讨了可生物降解的逆蜂结构的辅助性行为,揭示了3D打印产生的残余应力如何影响它们的变形. 有限元模拟准确地预测了这种应力及其对机械性能的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 增材制造 增材制造 增材制造
背景情况:
- 增材制造工艺,如沉积建模 (FDM),在可生物降解的聚合物结构中引入残余应力 (RS) 和扭曲.
- 反向蜂结构表现出辅助性质,但它们的行为可能受到制造引起的缺陷的影响.
- 在精细,复杂的结构中测量RS在实验上具有挑战性.
研究的目的:
- 为了研究5x5细胞逆蜂结构的辅助性拉伸变形行为,这些结构由可生物降解的聚乙烯基酸盐-甲酸盐 (PBAT) 制成.
- 以数值预测和分析残余应力 (RS) 对这些结构的辅热变形的影响.
- 为了将模拟预测与对曲面和变形行为的实验结果进行比较.
主要方法:
- 利用化沉积模型 (FDM) 来制造PBAT反向蜂标本.
- 采用基于有限元素 (FE) 的过程模拟 (ABAQUS插件) 来预测RS和曲面.
- 将预测的RS作为初始条件集成到FE模型中,以模拟辅助性拉伸行为.
主要成果:
- FE过程模拟准确地预测了与设计相对微不足道的偏差的曲面.
- FE模拟揭示了制造过程中温度演变和循环加热/冷却的影响.
- 分析显示,与非RS模拟相比,RS对力位移曲线,Poisson比率演变和应力分布有显著的影响.
结论:
- 基于FE的过程模拟是一种可行的方法,用于预测增材制造的辅助性结构中的RS和曲面.
- 其余应力显著改变PBAT逆蜂结构的辅助变形行为.
- 该研究提供了通过增材制造制造的可生物降解辅助性材料的机械性能.
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