High Temperature Adiabatic Heating in µ-IM Mould Cavities—A Case for Venting Design Solutions

Abstract

Micro-injection moulding (µ-IM) is a fabrication method that is used to produce miniature parts on a mass production scale. This work investigates how the process parameter settings result in adiabatic heating from gas trapped and rapidly compressed within the mould cavity. The heating of the resident air can result in the diesel effect within the cavity and this can degrade the polymer part in production and lead to damage of the mould. The study uses Autodesk Moldflow to simulate the process and identify accurate boundary conditions to be used in a gas law model to generate an informed prediction of temperatures within the moulding cavity. The results are then compared to physical experiments using the same processing parameters. Findings from the study show that without venting extreme temperature conditions can be present during the filling stage of the process and that venting solutions should be considered when using µ-IM.

Latest Advancements in Micro Nano Molding Technologies—Process Developments and Optimization, Materials, Applications, Key Enabling Technologies

“…(3) Tooling technologies and micro tool design. Wang et al [6] developed the air-shielding electrochemical micromachining (AS-EMM) process to improve the generation of microstructures on metal surfaces; Li et al [7] analyzed the effects of machining errors on the optical performance of optical aspheric components in ultra-precision diamond turning; Tucker et al [8] characterized different venting design solutions in micro molding tools and the influence of micro injection molding process parameters on air traps and adiabatic heating. (4) Applications.…”