Requirements for Developing Robust Plasma Spray Control for Production Operations

This paper examines the integrated control design and particle sensor requirements to achieve improved plasma spray manufacturing capabilities.  The analysis is based on results from a number of different production facilities that span different applications (TBC and fuel cells), different materials, equipment (conventional and high enthalpy systems), as well as emerging processes such as solution spray.  In addition to the direct control structure requirements, important considerations for deployment of particle sensing and control in manufacturing operations are provided.   A control hierarchy is developed to address important process objectives for both production (deposition rate, deposition efficiency, and compensating for process variation) and coating performance (structure and properties). The control design requirements and performance implications for both operator-based and automatic control are evaluated