【作者】 王继章；

【导师】 徐征；

【作者基本信息】 大连理工大学 ， 机械制造及其自动化， 2012， 硕士

【摘要】 微注塑成型具有周期短、效率高的特点,已经成为聚合物平板微器件的重要加工方法。翘曲是微注塑成型中的主要缺陷之一,直接影响到平板微器件的成型质量,以及后续的加工工序,翘曲控制已成为国内外学者的研究热点。此外,平板微器件的成型与键合相互分离,键合需要在专门的仪器设备上完成,增加了生产周期和成本,因此,高效的键合方法是平板微器件批量化生产的关键环节。本文以微注塑成型平板微器件为研究对象,从注塑残余应力的角度来研究翘曲变形的控制方法,利用仿真计算和测量实验,分析了注塑工艺参数对翘曲影响的权重顺序,以及工艺结构对残余应力分布和翘曲变形的改善作用,选择异丙醇为辅助溶剂,进行了模内键合实验。主要研究内容包括：设计了一套型芯可插拔式的微注塑模具。采用镶拼式结构,型芯采用硅为材料,利用MEMS工艺加工制作,金属模架部分借鉴常规模具的设计原则,设计了浇注系统、模温控制系统、排气系统和推出机构,设计了基于插板结构的装配方式,实现了模具型芯的快速无损装配。通过正交仿真试验,分析了注塑工艺参数及工艺结构对翘曲的影响。采用Moldflow软件研究了熔体温度、保压压力、保压时间、模具温度和冷却时间对翘曲的影响,优化了工艺参数；在相同工艺条件下,仿真分析了增加工艺结构对减小翘曲的影响,采用Ansys软件分析了工艺结构对注塑残余应力的改善作用。完成了平板微器件的翘曲测量实验。根据仿真试验内容,测量了不同工艺参数下平板微器件的翘曲值,比较了增加工艺结构前后,平板微器件翘曲变形的变化趋势,对仿真结果作了进一步验证。利用异丙醇完成了模内键合实验。测试了不同温度、时间条件下,PMMA芯片在异丙醇溶液中的溶胀作用,对微通道形貌和芯片表面粗糙度进行了观测,采用Babyplast610微型注塑机和微注塑模具作为键合平台,利用异丙醇进行键合实验,通过拉伸实验测试了芯片的键合强度,观察了键合后微通道截面形状,优化了键合工艺参数。更多还原

【Abstract】 As its short injection cycle and high efficiency, micro injection molding is an important fabrication method of polymer flat micro parts. Warpage is one of the major problems in micro injection molding, which could not only weaken the injection quality, but also affect the following working procedures. Thus, warpage has been a research focus for domestic and foreign scholars. For the fabrication of polymer flat micro parts, the bonding procedure should be conducted in special facilities and is separate from molding, which leads to long production cycle and high cost. Therefore, to develop an efficient bonding method is the key part in the mass production of polymer flat micro parts.In this paper, the micro injection molded polymer flat micro parts were taken as the research object, the warpage controlling method was developed in terms of the residual stress in micro injection. Through the simulation and the measurement experiment, the influence order of the process parameters on warpage was analyzed as well as the effect of technological structures on warpage improvement. Further more, the solvent-assisted in-mold bonding experiment was conducted based on isopropanol. The major contents are as follows:A core-removable micro injection mold was designed. The insert structure was selected and the Si chip was fabricated as the core by MEMS process. With the utilization of traditional design discipline, the gating system, mold temperature controlling system, exhaust system and ejection mechanism were implemented. And a removable assembling method was designed to realize the rapid and non-damaged replacement of mold core.With the Taguchi method in the simulation, it was analyzed that the influence of injection process parameters and technological structures on warpage. Moldflow was conducted to research the influence of melt temperature, packing pressure, mold temperature and cooling time on warpage. and optimize the parameters. Further more, the weakening effect of technological structures on warpage was analyzed in the same conditions. And its influence on residual stress improvement was studied by Ansys.The warpage measurement experiment was implemented. According to the simulation results, the warpage values were measured under different process parameters. And the change of warpage values was compared to the former one after adding the technological structures, in order to test the simulation conclusion. In-mold bonding experiment was completed based on the isopropanol solvent. The swelling of PMMA was tested under different temperatures and times in the isopropanol. and the micro channel shapes and surface roughness were measured. Besides, the in-mold bonding experiment was carried out with isopropanol on Babyplast610micro injection machine, the bonding strength was tested through tensile experiment, and the process parameters were optimized.更多还原