Abstract
In the improvement in durability of Thermal Barrier Coating (TBC) for gas turbines, thermal stress relief of ceramic topcoat and growth suppression of thermal growth oxide (TOO) formed on top/undercoat boundary are important technical subjects. In this paper, a trial production and a heat cycle test of the columnar structure TBC by EB-PVD advantageous to thermal stress relief were investigated. Furthermore, the growth process of TGO was investigated for the growth suppression. Consequently, the columnar structure TBC showed the excellent heat cycle durability compared with plasma sprayed TBC. It was shown that TGO is constituted by Yttrium containing Al_2O_3 matrix composite oxide layer and a nodular composite oxides.
