Improved Interface Coating Facility for Ceramic Composites

Synterials has in place a facility that will coat long lengths of ceramic cloth such as CG Nicalon with multilayer coatings based on the BN system. This coating capability is the first step in affordability. The next issue that needs to be addressed isreproducibility. This proposal directs effort at qualifying a sensor system that will determine the composition and the deposition rate of the coating process on-line. One candidate sensor has been evaluated in a preliminary manner and two others are tobe included in the study. To qualify the sensor system, it is proposed to capture, on-line, deposits that can be measured in about a minute without interrupting the coating of the cloth. This measurement will be made multiple times during the coating oflong lengths of cloth. The precision of the sensor will be evaluated by comparing the results of the sensor values with that measured by Auger and SEM on the same coating samples. Phase 2 will start once the precision of the sensor system has beenestablished. In Phase 2 multiple meter lengths of cloth will be processed with specified on and off design conditions and the cloth used to produce composite evaluation panels. These panels will be tested under various loading and environmentalconditions. In parallel with the sensor work will be work to fully automate the existing manual control system. This computer controlled system will include special warning and alarm features designed to assure the coating quality.Reproducible, low costinterface coatings are required to assure that the predicted properties of a given composite will be achieved in every similarly produced composite. This assurance that the properties used in a design will be faithfully produced in production compositesis essential for both military and commercial applications. This program represents an important step in moving a composite system from research to production.