Ultrasonic Injection and Cure Process Monitoring: Enhancing Efficiency and Quality Assurance

Abstract

Ultrasound-based process monitoring offers a notable advantage: transducers operate without direct contact with the part, preserving the integrity of part surfaces and mold vacuum tightness. In-house developed, small and low-cost transducers facilitate seamless integration in a high number - if necessary. Advanced signal analysis allows not only the detection of flow front arrival time but also its velocity. Previously, cure monitoring required through-transmission with a transducer on each side of the part to measure sound velocity for deriving cure degree. Recent findings indicate the possibility of cure monitoring using pulse-echo configuration, simplifying transducer integration not only for open-mold applications and allows cure monitoring in parts with sandwich reinforcement. In addition to pressure waves, lamb waves expand process monitoring capabilities and offer another alternative to the through-transmission method. The sensor system accelerates process development and design, enhances quality assurance, allows process automation and reduces non-destructive testing (NDT) effort.