EB-PVD process management for highly productive zirconia thermal barrier coating of turbine blades

Zirconia thermal barrier coatings are well used in the turbine manufacturin g industry because they ensure extended lifetimes of turbine blades. Compar ed with other techniques, EB-PVD processes are best suited for the depositi on on turbine blades with regard to the layer properties. Therefore EB-PVD coaters for turbine blades are becoming increasingly interesting. The coating costs per component are mainly dependent on a highly productive solution for the deposition task. Thus the EB-PVD process management has t o be optimized in order to meet the productivity requirements of the manufa cturers. This includes the requirement of high deposition rates, large depo sition areas, long time stable production cycles as well as a matched durat ion of preheating deposition and cooling down per charge duration of prehea ting, deposition and cooling down per charge. Modern EB-PVD solutions to be introduced allow deposition rates on blades u p to 7 mu m/min. The consequences for the technological process management and plant design concerning long time stable coating cycles with high produ ctivity will be discussed. (C) 1999 Elsevier Science S.A. All rights reserv ed.