Thermal Barrier Coating – Term Paper Example
Review on Thermal Barrier Coatings Introduction Escalating energy demands require design and development of novel materials and technologies. Generation and transportation of energy is predominantly done using gas turbines. For efficiency purposes, systems such as the Thermal Barrier Coatings (TBCs) have been incorporated into gas turbines (Osorio, Toro& Hernández-Ortiz 149). Typically, TBBs are used to provide thermal insulation for components of metallic that are emitted by the combustion gases, leading to a reduction in the substrate temperature from around 1000C to around 3000. The TBCs are made of excellent mechanical properties and provide rupture and corrosion resistance at very high temperatures. While in application, the material of TBCs changes its behavior. The top coat sinters as it changes its mechanical properties as well as its thermal conductivity. Additionally, when exposed to high temperatures the oxidation and microstructural changes due the depletion of elements. Normally, exposure to high temperatures makes the mechanical and thermal loading increases the level of residual pressure existing at the interface between the metal and the ceramic. With time, in terms of interface delamination will raise within the material system. Ultimately, the delamination damage becomes so severe that the material buckles and large pieces of the top coat (TC) flake off. As a consequence of the diminishing coat, the underlying metal starts to overheat with an obvious risk of severe oxidation as well as leading to creep-damage if the component is stressed up mechanically (Brodin et al.). To use a gas turbine in an economic and an effective way, it is advantageous to maximize the time between overhaul and inspections with maintained mechanical integrity. Therefore, a variety of different tools is used to assess the spallation fatigue life for all thermal barrier coatings. This review paper seeks to look into the use of thermal coating, and how it functions in such uses. Further, this review paper highlights different ways how thermal coating is produced, and finally it discusses some possible application of Thermal coating.
Brodin,H., Jinnestrand, M., Johansson, S,& Sjöström,S. Thermal Barrier Coating
Fatigue Life Assessment.Viewed 11th June 2015.
Osorio, J, Toro, A, & Hernández-Ortiz, J. Thermal Barrier Coatings for Gas Turbine
Applications: Failure Mechanisms and Key Microstructural Features. 2012. Viewed 11th June 2015. < http://www.scielo.org.co/pdf/dyna/v79n176/v79n176a18.pdf>.