微型挤出过程中熔体流变行为的模拟分析

摘要

The structure features of the micro-extrusion spray head used in fused deposition modeling system were introduced firstly, then the melt theological behavior in the screw and nozzle was simulated respectively by Polyflow to get the factors which influenced the melt rheological behavior. The result showed that the melt flow rate was heavily influenced by the screw rotate speed, nozzle pressure was lost mainly around the die, and there were melt stagnation areas near the barrel wall in the nozzle.%首先介绍了应用于熔融沉积快速成型中的微型挤出喷头的结构特点;随后根据微型螺杆的挤出特性,分别对螺杆段和口模段的熔体流变行为进行模拟分析,从而得出影响熔体流变行为的因素.结果表明,熔体流率受螺杆转速影响较大,压力降主要出现在口模附近,在喷嘴中靠近壁面处存在熔体滞留区.