Gas Turbine Thermal Barrier Coating

Failure mechanisms and key microstructural features recubrimientos de barrera térmica para aplicación en turbinas a gas.

Gas turbine thermal barrier coating.

Universidad nacional de colombia medellín colombia jdosorio unal edu co. Functionally graded materials 1996 1997. The thickness of the zirconia required depends upon the gas stream temperature and the amount of cooling available. The use of tbcs 100 to 500 μm in thickness along with internal.

Nonetheless thermal barrier coatings tbcs made of low thermal conductivity ceramics are now being used to provide thermal insulation to metallic components from the hot gas stream in gas turbine engines used for aircraft propulsion power generation and marine propulsion. Tbcs which comprise metal and ceramic multilayers insulate turbine and combustor engine components from the hot gas stream and improve the durability. Thermal spray coatings for industrial gas turbines produce substantial benefits. As already stated above the power to weight ratio and efficiency of gas turbine engines are limited to the burn temperature they can run at which is caused by the limit of suitable materials available to use in a turbine engine if the burn temperature is raised at to high a temperature then the rotor and stator blades will melt.

A second type of coatings applied to high temperature parts are known as thermal barrier coatings tbc. Thermal barrier coatings tbcs are widely used in hot sections of gas turbine engines to improve their operating temperature and provide thermal protection for the underlying metallic components thereby improving the efficiency and performance of the engine. Of all these thermal barrier coatings tbcs have the most complex structure and must operate in the most demanding high temperature environment of aircraft and industrial gas turbine engines. Coatings for combustion liners are normally specified by the turbine manufacturer.

These coatings can be applied to a thickness of 2 mm although typical thickness is in the range of 0 2 mm to 0 5 mm. Thermal barrier coatings tbcs are advanced materials systems usually applied to metallic surfaces operating at elevated temperatures such as gas turbine or aero engine parts as a form of exhaust heat management these 100 μm to 2 mm thick coatings of thermally insulating materials serve to insulate components from large and prolonged heat loads and can sustain an appreciable temperature. These are ceramic coatings with very low thermal conductivity. Mecanismos de falla y principales características microestructurales julian d.

The gas path of these parts are coated with a thermal barrier coating typically consisting of a metallic layer called the bond coat made of a material referred to as an mcraly an alloy of metals like nickel or cobalt or some combination thereof and.