模壁粗糙度对微注塑成型充模流动的影响研究
PDF下载 (237)虞 磊,陈 兴,王 英.模壁粗糙度对微注塑成型充模流动的影响研究[J].宁波大学学报(理工版),2023,36(6):42-49.DOI:10.20098/j.cnki.1001-5132.2023.0422
YU Lei,CHEN Xing,WANG Ying.influence of mold wall roughness on mold filling flow in micro-injection molding[J].Journal of Ningbo University(Natural Science & Engineering Edition),2023,36(6):42-49.DOI:10.20098/j.cnki.1001-5132.2023.0422
| Title: | influence of mold wall roughness on mold filling flow in micro-injection molding |
| 作者: | 虞 磊, 陈 兴, 王 英 |
| Author(s): | YU Lei, CHEN Xing, WANG Ying |
| 关键词: | 表面粗糙度; 微注塑; 仿真模拟; 流变数据 |
| Keywords: | surface roughness; micro injection; simulation; rheological data |
| 分类号: | TQ320.66 |
| DOI: | 10.20098/j.cnki.1001-5132.2023.0422 |
| 文献标识码: | A |
| 摘要: | 模壁粗糙度对微注塑成型的充模过程有着十分重要的作用, 本文从微尺度流中塑料熔体的可压缩性充模模型出发, 对模具内壁粗糙度进行了讨论和简化, 并通过连续性方程、动量守恒方程和能量守恒方程给出了考虑模具表面粗糙度的充模控制方程, 采用有限元/有限差分法来求解充模中的压力、温度等, 采用修正的Cross-WLF模型表征熔融塑料材料的非牛顿行为流变特性. 通过数值模拟, 分析了模壁粗糙度对充模流动的影响, 并设计一系列实验, 考察各种工艺参数情况下模壁粗糙度对充模流动的影响. 模拟和实验结果表明 型腔厚度越小, 模壁粗糙度对充模流动的影响越显著; 熔体温度越低, 模壁粗糙度对充模流动的影响越显著; 注射速率对模具表面粗糙度效应影响较小. |
| Abstract: | The roughness of mold wall plays a very important role in the filling process of micro-injection molding. Based on the filling model of plastic melt in micro-scale flow, the dimension of mold inner wall roughness is discussed and simplified. The governing equation considering mold surface roughness is given through continuity equation, momentum conservation equation and energy conservation equation. The pressure and temperature in the filling process are solved by finite element/finite difference method, and the rheological characteristics of non-Newtonian behavior of plastic melting are characterized by modified Cross-WLF model. Through numerical simulation, the influence of mold wall roughness on mold filling flow is analyzed, and a series of experiments are designed to investigate the influence of mold wall roughness on mold filling flow under various process parameters. Both simulated and experimental results show that the smaller the cavity thickness, the more significant the influence of mold wall roughness on mold filling flow; the lower the melt temperature, the more significant the influence of mold wall roughness on mold filling flow. In addition, the experimental results also show that the injection rate has little effect on the effect of the mold surface roughness in the mold filling. |
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| 备注/Memo: | 收稿日期:2023-04-20.宁波大学学报(理工版)网址:http://journallg.nbu.edu.cn/ 基金项目:宁波市重大科技攻关暨“揭榜挂帅”项目(2022Z009,2022Z063). 第一作者:虞磊(1995-),男,浙江宁波人,在读硕士研究生,主要研究方向:微注塑成型.E-mail:360487912@qq.com *通信作者:陈兴(1963-),男,湖南茶陵人,博士/副教授,主要研究方向:材料成型CAD/CAE.E-mail:chenxing@nbu.edu.cn 宁波大学学报(理工版)网址:http://journallg.nbu.edu.cn/ |