This research project addresses a major processing obstacle to the development and commercialization of high temperature ceramic and metal matrix composites (CMC/MMC) for both military and industrial applications. Interface coatings are required to avoid reaction between fiber and matrix portions of the composites, thereby permitting translation of the fiber reinforcing characteristics to the matrix component. The lack of adequate control over the coating of fibers by Chemical Vapor Deposition (CVD) continues to hinder progress in this field. Appropriate process sensors are a necessity in pursuing real process control and, ultimately, intelligent processing. In a prior Phase 2 program, funded by the Air Force, ATMI identified several combined FTIR techniques that provided excellent diagnostic capabilities for the CVD fiber coating process. ATMI also made significant progress in establishing the hardware and software infrastructure necessary to integrate such sensors into the process. Although several FTIR tools were purchased, their integration with the process remains to be performed. ATMI will integrate FTIR tools, for on-line gas and coating analysis, with its computer-controlled CVD fiber coating process. Key features of the FTIR spectra from the exhaust gas and/or the coatings will be related to specific input parameters and a simple model will be constructed. In Phase II, the model will be expanded and used to establish closed-loop control over the CVD process, guided by a computer-run algorithm
