Micro-injection Molding Mechanism And Process Technology For High Aspect Ratio Polymer Elements

With the development of micro-and nanotechnology, micro-polymer elementsare widely used in a variety of micro-system products. their main processingmethod—micro-injection molding also attracts extensive attention. The rapiddevelopment of polymer elements with micro-features brings new challenges. Thearticle focuses on the clamping device of micro-injection molding machine and thetechnology of micro-injection for high aspect ratio micro polymer elements.Because of the large entire size of the clamping mechanism and the long flowchannel，traditional injection molding machine wastes a lot of material and energy.But if the size of the clamping mechanism is reduced, new problems will occur, suchas the insufficient champing force and strength. Based on the theoretical analysis forthe kinematics characteristics and mechanical properties of the elbow rob clampingmechanism for the micro-injection molding machine, the optimal geometricparameters were determined, and kinematics simulation and static analysis for theelbow rod were carried out. The results showed that the design of elbow rod champingmechanism of micro-injection molding machine meet the ideal slow-fast-slow speedcharacteristics. And it was able to meet the premise of10t clamping force requirementand provided sufficient rigidity and strength.During the micro-injection molding process, the experiments of micro-needlearrays micro-injection molding assisted by ultrasonic wave were designed to solvemold filling discontent problem during the micro-injection molding. Experiments ofmicro-needle arrays (6μm and100μm) were conducted through the self-developedmold device with ultrasonic wave, it was found that the ultrasonic wave has a goodeffect on the filling. The contribution rates of process parameters, such as moldtemperature, melt temperature, injection velocity, holding pressure and ultrasonicassistance, were ranked though orthogonal tests with the100μm diametermicro-injection. Through all above, a new thinking was developed to solve theproblem of filling discontent problem during the micro-injection molding.