Mineral polymer tooling system for making prototype fibre reinfoced composite parts

Abstract

In the plastic and composite manufacturing industry the “time to market” and special, small series are getting increasingly important.When the production of a part is limited to a prototype or a small quantity, most conventional mould/tooling systems are either too expensive and take too much time to be build, or can not cope with the surface finish, production technology and raw materials of the future mass product.At the “Vrije Universiteit Brussel” (Belgium) new ceramic materials so called “Mineral Polymers (MiP)” are being developed. These inorganic materials can be cast, and are hardening out at atmospheric pressure and low temperature: between 15°C and 100°C. They present some attractive characteristics like low material cost, low shrinkage, low thermal expansion, fire incombustibility, high temperature resistance (up to 1200°C) and mechanical properties somewhere between those of technical ceramics and concrete.The interesting properties of mineral polymers make them well suited for prototype moulding. The mould can easily be made by pouring mineral polymer over the wax, plastic or plaster model, fitted with all inserts such as closure system, ejectors, heating and cooling devices. It is possible, by changing the amount and type of fillers and fibres, to tune the mechanical and thermal properties of the mineral polymers.The research work is focused on a number of fibre reinforced composite manufacturing processes, like: RTM, autoclave, RIM, SMC, BMC and injection. For each process a tooling system was worked out on material level. Moulds were made and tested out for prototype parts such as a three spoke bicycle wheel, a wheelchair wheel, fins for wind surfing, a part of a car body and some flat, box, curved and tube like test objects.