In a project financed by BMBF- (Federal Ministry of Education and Research) the ultrasound sensors and technology were employed to monitor the resin transfer molding (RTM) of large fibre reinforced moulded parts.
Ultrasonic sensor system, RTM process (sheme) (enlarged picture)
Knowledge and control of the flow behaviour of the resin system in the mould is essential to optimise and control production. Large moulds can be equipped with several sensor lines, which can be monitored simultaneously using a multiplexer control system. This enables the processor to monitor the flow front as well as the cure reaction at several different positions in the mould. In this manner, it is possible to literally visualise in-situ mould filling and the degree of cure.
Resin transfer molding (RTM), mould with sensors (enlarged picture)
The measurement results provide the plastic processor with important information in relation to process progression and optimisation.
Like any technology developed for specialised application, it is necessary to provide a qualified appraisal using conventional laboratory techniques. The ultrasound group co-operated closely with BAM Department VI Materials Protection and Surface Technologies and the results from several polymer analytical techniques including DMA and DSC were taken into consideration.
Division 8.4 | Material Characterization Using Ultrasound
