Force Sensing Resistors For Monitoring Laminate Consolidation Pressure

Heat and pressure are the two most important control variables in composite processing. Temperature control is managed with thermocouple sensors. Laminate consolidation can now be measured using force sensing resistors. The sensor is less than 0.012 inches (0.3mm) thick and can accurately measure lamination pressures up to 200psi at 500 degrees F. Applications include vacuum bag leak detection, pressure measurement in expansion tools, resin transfer molding, compression molding, and pultrusion. The sensor has been used in the aggressive environment of a pultrusion die to monitor the pressure profile of epoxy, phenolic, and polyester reinforced composites. Differences in the pressure profile of each resin indicate important process considerations.