Dielectric Cure Monitoring technology
Dielectric Cure Monitoring research efforts include various adaptations of the developed process monitoring and control system for composite materials manufacturing. INASCO is leading European Consortia in the projects CondiComp (FP5), COMPROME and SENARIO (FP6) and has developed dedicated hardware, software and algorithms for the cure modeling and monitoring in composites processing and adhesive bonding processes, which are commercially available.
The main feature of the monitoring system utilizing in-process dielectric sensors is the capability to extract material state information from the sensor response. The measurement hardware (see also DiAMon plus TM system) is only a part of INASCO monitoring philosophy, which has wide range applications in all areas of materials transformation (manufacturing, bonding, recycling, etc.).
The new commercial injection machine (see picture below) which is implemented by INASCO is interfaced with flow and cure simulation tools for integrated control of the manufacturing process.
A particular example of the utility of the monitoring system in industrial control equipment is the integration of the ISOJET Equipements injection control system with new Fieldpoint modules and the dielectric data acquisition system from sensors in the resin pot and in the closed mould. Tool mounted in-process dielectric sensor for resin flow and cure monitoring in RTM processing, measurement system and monitoring software are shown.
The potential of INASCO monitoring approach lies in the control of the manufacturing process through guidance of the basic material properties, such as the Degree of Cure, over a predefined path (yielding optimal process parameters, cost effectiveness and quality control). Various industrial implementations of the monitoring technology have been achieved including:
  • the development of a resin arrival detection system dedicated to ISOJET Equipements injection control machines
  • the installation of a complete monitoring, quality assessment and control system for aerospace grade pultrusion processing for Exel Composites UK

Pultrusion monitoring system and installed dielectric sensor for quality control
of continuous processing of composite materials
  • the sensor installation and the monitoring of resin viscosity in injection tank and the prediction of available injection time in RTM and RTI processing for Bombardier Aerospace – Shorts in UK.
  • the integration of sensors in a mat for monitoring the cure of adhesive and patch in bonding repair processes

Sensing mat bearing 2 dielectric sensors for the monitoring of patch cure
during adhesive bonding repair of metallic structures

Other applications of the process monitoring and control technology in composites manufacturing include:
  • Resin transfer moulding (RTM)
  • Liquid resin infusion
  • Autoclave processing
  • Filament winding

Additional R&D activities on manufacturing processes by INASCO address the area of knowledge capture within a Virtual Institute for Composite Materials (by the ERIC consortium) and the microscale fabrication of graded materials by laser sintering technologies (MICROMAKING project technology).