This Small Business Innovation Research (SBIR) Phase I project will develop a system to characterize the high velocity oxygen fuel (HVOF) coating process that will enable reduction of coating variation. Recent innovations in materials engineering have resulted superior coatings for wear protection in terms of stress, density, and hardness. However, variation in the coating process has limited process capability and slowed process development. This new system will detect process variation and compensate for it before coatings are deposited and streamline development by quickly characterizing new process operating points. The Phase I project will focus on developing the capability to sense process variation and identify methods for compensating for this variation. The sensor will build on technology already developed for the plasma spray coating process which enables rapid characterization of the process at speeds satisfactory for production coating shops. The new system will be specifically developed to support coatings of recently developed nanocomposite powders, for which rapid process development and consistent application are extremely valuable.
The broader impact/commercial potential of this project will be realized in the $1.5 billion HVOF coating market, which is growing rapidly after 2007 OSHA regulations limited worker exposure to hexavalent chromium. HVOF has been validated as the primary replacement for the environmentally hazardous hard-chrome process and the largest applications are wear coatings for aircraft landing gear, but alternative applications include wear and corrosion coatings for industrial equipment and biocompatible coatings for medical devices. New nanocomposite powders are improving performance of these coatings beyond their current capabilities but the current levels of variation in the HVOF process are unacceptable for reliably achieving this performance. Customers for HVOF coatings have insisted that coating suppliers implement sensors, but the available sensors are difficult to use and the information that they provide does not always correlate to the relevant coating characteristics. This project's sensing and control system fills that gap by providing both an easy to use sensor and a semi-automatic way to use the sensor data. It is anticipated that this control system will capture the significant number of sprayers who are required to make process improvements, but are frustrated with the available equipment and methodologies.
