Industrial interest in micro fabrication techniques has mushroomed in the wake of recent advances in microtechnology, notably the LIGA technique, which provides a cheap and effective route to the mass fabrication of complex microstructures. At the heart of LIGA technology is the injection moulding process. It is generally accepted that computer aided modelling has superseded the trial and error methods that once characterised the design stage of injection moulding. Computer modelling is now relied upon to help design the mould, runners and gates, and to define and optimise a host of process parameters. However, current state of the art software has many drawbacks when applied to microinjection moulding, since the current 2D approach is fatally flawed when modelling structures, which have large surface to volume ratios. In addition, the small space and time scales governing the filling of micro structures strongly modify the physics of the flow.
There is therefore a strong need for new and reliable models, together with improved physical knowledge of the process. The objectives of this project are: Development of a 3D mathematical and numerical model for the simulation of the filling stage of micro injection moulding; Acquisition of experimental evidence concerning the physical phenomena governing the process; Design of improved tools specifically targeted at micro injection moulding; Selection and analysis of engineering polymers for micro injection moulding; Assessment of the new integrated process using a complex industrial demonstrator micro part; Development of a completely new methodology to predict the quality of the parts. The consortium comprises a micromechanics institute (IMM), a university applied mechanics unit (UCL), an electronics components manufacturer (Oxley) and an engineering polymer producer (Phillips).
Funding SchemeCSC - Cost-sharing contracts