聚合甲利胺泡的压缩机械行为和相应的故障机制是由热机械合诱导的
Zeyang Xing1, Qianying Cen1, Qingyou Wang2
1School of Aerospace Engineering & Applied Mechanics, Tongji University, Shanghai 200092, China.
Polymers
|May 11, 2024
概括
聚米甲利胺 (PMI) 泡的机械性能和故障机制在20-120°C之间进行了研究. 压缩产量应力和模量随着温度的增加而显著降低,将故障从脆性骨折转移到塑料产量.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 机械工程 机械工程
背景情况:
- 聚合物泡成型中的热机械合可以诱导压缩产量,影响最终产品质量.
- 了解在成型温度范围内的聚合甲利胺 (PMI) 泡的行为对于结构完整性至关重要.
研究的目的:
- 研究PMI泡在20°C至120°C的压力力学特性和故障机制.
- 分析温度对PMI泡的屈服应力,弹性模量和故障模式的影响.
- 探索内部空气压力在脆性-塑料过渡期间泡行为上的作用.
主要方法:
- 动态机械分析 (DMA) 和热重力测量分析 (TGA) 用于评估热稳定性和机械损耗.
- 在各种温度 (20-120°C) 下进行压缩测试,以确定机械性能和故障模式.
- 微计算机断层扫描 (Micro-CT) 和3D重建 (Avizo) 创建实体代表体积元素 (rRVEs) 用于有限元素分析.
主要成果:
- PMI泡在20-120°C范围内表现出最小的机械损耗和热稳定性.
- 屈服应力和弹性模量随着温度的增加而下降;在120°C时,它们相比20°C下降分别为35.2%和31.4%.
- 故障模式从20°C的脆裂转变为120°C的塑料产量,过渡区在80°C左右.
- 模拟证实了取决于温度的故障模式,内部空气压力在80°C时影响产量应力约6.7%.
结论:
- PMI泡的机械性能随着成型范围内的温度升高而显著降低.
- 从脆性骨折过渡到塑料产量是一个关键的现象,发生在80°C左右.
- 内部空气压力在PMI泡的产量行为中起着显著的作用,特别是在脆性-塑料过渡温度附近.
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