摘要
基于流变学基本方程和PTT本构方程,建立了三维粘弹曲线型塑料异型材包覆共挤成型数值模型,运用有限元方法对数值模型进行了模拟计算,分析研究了气体辅助工艺对曲线型异型材共挤成型过程中挤出胀大、扭曲变形及口模内流场分布的影响。研究结果表明,传统共挤成型时,共挤制品的挤出胀大及变形、口模内熔体速度场、压力场、剪切速率及应力场等的分布均随着壳层熔体黏度的变化而变化,而气辅共挤成型时,共挤制品的挤出胀大和变形现象以及口模内熔体流场的分布均与芯壳层熔体的物性无关,能实现制品截面形状和尺寸与口模截面形状和尺寸保持一致的精密共挤。
The three-dimensional viscoelastic multiphase gas-assisted co-extrusion mathematical models established through a curved profile channel based on the basic equations of rh^eology and PTT model equation were numerical simulations were presented by the finite element method. The results were analyzed to reveal the influence of the gas-assisted process on die swell, deformation and flow field in the die in the curved plastic profile co-extrusion molding. The results show that in the traditional co-extrusion, the polymer melt characteristics have a great effect on die swell, deformation, velocity distribution, pressure distribution, shear-rate distribution, stress distribution and so on. However, in the gas-assisted co-extrusion, the polymer melt characteristics have little effect on die swell, deformation and flow field in the die. The gas-assisted process can match the shape and size of products to one of the die cross section.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2015年第11期119-123,共5页
Polymer Materials Science & Engineering
基金
国家自然科学基金资助项目(51163011)
江西省青年科学基金(20122BAB216012)
关键词
曲线型异型材
气辅共挤
粘弹性
挤出胀大
数值模拟
curved profile
gas-assisted co-extrusion
viscoelastic
die swell
numerical simulation
