在局部加热器的方向绘图期间,在聚合物片中估计热流量
Liubov Myasnikova1, Yuri Kurakin2, Vladimir Hilarov1
1Laboratory of Physics of Strength, Ioffe Institute, Politekhnicheskaya 26, 194021 St. Petersburg, Russia.
Polymers
|August 29, 2024
概括
研究用局部加热器绘制的聚合物薄膜显示,不均的加热会导致显著的强度差异. 较薄的薄膜 (<50微米) 确保温度分布均,以获得最佳的纤维特性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 机械工程 机械工程
背景情况:
- 用局部加热器对聚合物薄膜的定向绘制对于生产高强度纤维至关重要.
- 一个关键的挑战是理论强度预测与实际纤维强度之间的差异.
- 这种差异与局部加热期间在薄膜上的温度梯度有关.
研究的目的:
- 为了研究单边加热对聚合物薄膜绘制的影响.
- 分析温度差异与塑料变形速率之间的关系.
- 为了确定优化聚合物纤维强度的最佳加工参数.
主要方法:
- 在聚合物薄膜中的热导和温度分布的数值计算.
- 在绘制过程中对薄膜厚度和宽度的温度梯度的分析.
- 温度均性与薄膜厚度和绘制速度的相关性.
主要成果:
- 薄膜表面之间的微小温度差异 (1°C) 可以显著改变塑料变形速率.
- 拉伸应力集中在较冷的侧面,可能产生缺陷和微裂.
- 对于纤维结构转换至关重要的均温度分布,只有在薄膜厚度小于50μm时才能实现.
结论:
- 在局部加热器绘制过程中单边加热会导致不均的变形和缺陷.
- 薄膜厚度是一个关键参数,<50μm是均温度分布的最佳值.
- 这项研究为优化像UHMWPE.PE.这样的高性能聚合物纤维的绘制速度和薄膜厚度提供了科学基础.
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