Thermal-Barrier Coatings with an External Magnetron-Sputtered Ceramic Layer for High-Temperature Nickel Alloy Turbine Blades

Abstract

The results of laboratory isothermal and cyclic heat-resistance tests of ion-plasma thermal-barrier NiCrAlY (Re, Ta, Hf) + AlNiY (Hf) + ZrYGdO coatings, which were applied on samples of high-temperature VZhM-4 alloy containing rhenium plus ruthenium, VZhM5Y alloy containing rhenium, and intermetallic VKNA-1V alloy, are reported. An external ceramic layer of thermal-barrier coatings (TBCs) is applied by the magnetron sputtering of Y- and Gd-containing zirconium alloy targets and has a columnar structure. The effect of TBCs on the long-term strength at a test temperature of 1000°C and on the high-cycle fatigue at 900°C is studied. It is shown that, according to the test results, the minimum damages of the ceramic layer and the minimum mass losses are observed for the VSDP-41 + VSDP-16 + VTsS-4 coating applied on the high-temperatures alloys and the VSDP-4 + VSDP-23 + VTsS-4 coating applied on the intermetallic alloy.