Sensors for Carbonization Control

Abstract

Phase I of “Research on Intelligent Processing of Carbon-Carbon Composites” is a two year program to develop enabling technologies for real time control of the carbonization process for resin matrix composites. The research has three related foci: in situ material property sensors; process models; and intelligent control architecture. The research has, to date, 1) developed control strategies at three levels of sophistication that use sensors and models to complete carbonization more rapidly while still reducing losses; 2) developed a control architecture that integrates those sensors and models; 3) conducted successful in situ tests of chemical and physical property sensors; 4) developed a high temperature eddy current sensor (not yet tested in situ); 5) developed considerable kinetic data on the carbonization reactions, described the basic reaction paths and their relation to physical properties qualitatively, and developed a kinetic equation for the lowest temperature family of carbonization reactions, the production of water from hydroxyl groups; 6) defined the modeling strategy for calculating gas pressure and the experimental strategy for developing models for matrix strength. In the following, we describe the general problem and the issues in modeling and control to provide a context for the sensor results.