多场耦合作用下模内组装成型机理及其形性协同调控机制

The micro-molding and micro-assembly are the common technical issues of micro or tiny mechanical systems manufacturing,and the advanced in-mold assembly molding technology that was invented by American in recent years is expected to resolve the common technical issues，which attracted recently much attention in the international arena. But, polymer micro or tiny mechanical systems in-mold assembly molding technology is still in the unscientific status of fumble manufacturing, its technical bottleneck encountered in transforming process to large-scale industrialized and scientific manufacturing is the precise controlling shape of thermal fluid-structure coupling deformation and the precise controlling characteristic in order to inhibit micro assembly interface adhesion of kinematic pairs in molding process.Against the key scientific issues， the project intends to: (1) study the thermal fluid-structure multi-field two-way coupling mechanism between viscoelastic melt flow and polymer elastic-viscoplastic deformed structure and thermal fluid-structure coupling deformation theory , and establish the computer simulation method for polymer micro or tiny mechanical systems in-mold assembly molding process; (2) study the precision control principles and technology of thermal fluid-structure coupling deformation based on gas assisted back pressure ; (3) study polymer chains diffusion and entanglement in micro assembly interface of kinematic pairs under the multi-field synergistic effect environment of molding flow, establish the thermodynamic and dynamic conditions of interface adhesion, put forward the control principles and technology of adhesion characteristics in order to inhibit micro assembly interface adhesion of kinematic pairs in molding process. The whole process comprehensive controlling industrialized and scientific manufacturing technology of polymer micro or tiny mechanical systems In-mold assembly molding was developed eventually with independent intellectual property rights.

微成型和微装配是微小型机械系统制造的共性技术问题，而美国近年发明的模内组装成型先进技术有望解决该共性技术问题，在国际上倍受关注。但至今聚合物微小型机械系统的模内组装成型技术仍处于摸索制造的不科学状态，在向工业化科学制造转变所面临的技术瓶颈问题是成型中热-流-固耦合变形的精确控形与抑制运动副微装配面熔接粘附的精确控性。针对关键科学问题，本项目将：1）研究黏弹性熔体流动与弹性-黏塑性聚合物变形固体的热-流-固双向耦合作用机理及其耦合变形理论，构建聚合物微小型机械系统模内组装成型过程的模拟方法；2）研究基于气辅背压的精密控形原理与技术；3）研究成型流动多场协同作用下运动副微装配面分子链的扩散与缠结行为，建立粘附形成的热力学与动力学条件，提出抑制运动副微装配面粘附的控性原理与技术。最终研发具有自主知识产权的全流程综合控制的聚合物微小型机械系统模内组装成型的工业化科学制造技术。

针对微小型机械系统微成型和微装配制造的共性技术问题，系统开展了模内微装配成型理论与技术研究，研究构建了描述微型零件边界变形运动与高温黏弹性熔体充填流动的多场协同双向热流固耦合作用的模内微装配成型机理的数理模型及其模拟技术，建立了成型过程参数、聚合物性能参数—成型充填流动流场、应力场—热流固热黏弹塑性变形、微装配界面可运动性能映射关联关系，揭示了预成型微型件产生热流固热黏弹塑性变形和熔接粘附微装配界面脱粘的机理。研究结果表明预成型微型件在充填流动环境下,其热流固热黏弹塑性变形受控于微装配界面的耦合压力、黏性拖曳剪切应力和弹性支撑正应力，而微装配界面可运动性能受控于熔接粘附微装配界面的脱粘驱动力和法向收缩自紧可运动驱动摩擦阻力。沿模腔壁面和微装配界面的熔体充填流动的壁面滑移，可以使微装配界面的耦合压力、黏性拖曳剪切应力、熔接粘附脱粘驱动力和法向收缩自紧可运动驱动摩擦阻力大幅降低，以此研究提出了高速自润滑液膜辅助模内微装配成型精密控形的创新原理与技术，实现了高性能聚合物精密微型机械模内微装配成型热流固耦合变形和可运动性能的精密控形控性的可控制造，为研发具有自主知识产权的全流程综合控制的聚合物微小型机械系统模内组装成型的工业化科学制造技术奠定了科学的理论基础和技术支撑。