THE EFFECT OF THE THERMAL EXPANSION OF THE RUBBER MOULD ON THE PRESSURE FORMING OF THERMOPLASTICS

摘要

Rubber pressing of thermoplastics is a fabrication process that allows the series production of composite parts with high mechanical properties. Its limited implementation in aircraft industry is caused by the lack of knowledge and the lack of proper design and process tools and manufacturing techniques. In particular the large amount of time spent in de definition of the suitable rubber mould, normally made based on the craftsmanship of the manufacturing engineer and material supplier, leads to the decision of producing very simple parts, mainly flat plates or single curved panels to avoid long development periods. The present paper describes the effect of the thermal expansion of the rubber mould on the pressure distribution. The deformations of the mould due to the change in temperature during the process and the consequent change in pressure distribution on the product during production are evaluated by means of static experiments. The influence of lubricant on the pressure distribution is investigated.