Thermal barrier coatings (TBC) are used widely on a range of components that operate at high temperatures. We report measurement of the factor that is required to convert the Raman shift to stress for air plasma sprayed yttria (7 wt %) stabilized tetragonal zirconia (ZrO(2)) (YSZ) thermal barrier coatings. The factor is evaluated for the as-coated condition and also following a heat treatment a...

In this article, failure and fracture mechanisms in an aluminum alloy (which has been used in diesel internal combustion engines), with and without ceramic thermal barrier coatings, have been investigated under isothermal and non-isothermal fatigue loadings. In this research, the base material is an aluminum-silicon-magnesium alloy and the thermal barrier coating includes a metallic bond coat l...

Problems of adherence of thermal protective coatings to aerospace structures have become important with their use on vehicles such as the space shuttle and for jet engine turbine blades. In these structures a dielectric coating which acts as a thermal barrier. is bonded to a conductive substrate. Failure of these coatings to adhere to the substrate can result in catastrophic failure of the vehi...

In fossil fuel power generation plants, steam generation tubes and turbine blades are critical for overall performance of plant. The materials are subjected to bear heavy wear and temperature during operation. The manufacturer has an option of using high wear resistant and high temperature materials which are costlier or using cheaper materials with ceramic coatings over it. The coatings expose...

Abstract Suspension plasma spraying (SPS) and spray-physical vapor deposition (PS-PVD) are the only thermal spray technologies shown to be capable of producing TBCs with columnar microstructures similar electron beam-physical (EB-PVD) process but at higher rates relatively lower costs. The objective this study was achieve fundamental understanding effect different produced by these two processe...

When tailored to make durable thermal barrier coatings (TBCs), the Solution Precursor Plasma Spray (SPPS) process produces a microstructure containing uniformly vertical cracks. These cracks provide a high degree of strain tolerance to the ceramic top coat. In order to understand the formation of vertical crack in SPPS process, coatings of various thicknesses were deposited on a variety of subs...

Ceramic Thermal Barrier Coatings (TBCs) on superalloy components are being used successfully in land-based gas turbine and aircraft engines. These coatings are generally made by either air plasma spraying (APS) or electron beam physical vapour deposition (EB-PVD). In general, EB-PVD TBCs have superior durability due to the columnar structure, but they are very expensive compared to APS TBCs. EB...

The thermal conductivity of yttria-stabilized zirconia (YSZ) thermal barrier coatings increases with high-temperature aging. This common observation has been attributed to the densification of the coatings as porosity sinters out and pores and cracks spheroidize to minimize their surface energy. We show that the thermal conductivity of fully-dense 3 mol.% Y2O3 stabilized zirconia (3YSZ) also in...