Failures of Turbine Components

Mapping Intimacies ◽

10.31399/asm.hb.v11a.a0006824 ◽

2021 ◽

pp. 512-530

Author(s):

Kevin Wiens

Keyword(s):

High Temperature ◽

Gas Turbines ◽

High Temperature Oxidation ◽

Erosive Wear ◽

Fretting Wear ◽

Temperature Oxidation ◽

Thermal Mechanical Fatigue ◽

Failure Investigation ◽

Industrial Gas Turbines ◽

Steam Turbine Blade

Abstract This article focuses on common failures of the components associated with the flow path of industrial gas turbines. Examples of steam turbine blade failures are also discussed, because these components share some similarities with gas turbine blading. Some of the analytical methods used in the laboratory portion of the failure investigation are mentioned in the failure examples. The topics covered are creep, localized overheating, thermal-mechanical fatigue, high-cycle fatigue, fretting wear, erosive wear, high-temperature oxidation, hot corrosion, liquid metal embrittlement, and manufacturing and repair deficiencies.

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The Effect of Laser Glazing on High Temperature Oxidation Resistance of Thermal Barrier Coatings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.315 ◽

2012 ◽

Vol 433-440 ◽

pp. 315-318

Author(s):

Seyid Fehmi Diltemiz ◽

Melih Cemal Kushan

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

Thermal Barrier Coatings ◽

Gas Turbines ◽

High Temperature Oxidation ◽

304 Stainless Steel ◽

Thermal Barrier ◽

Laser Glazing ◽

Temperature Oxidation ◽

Barrier Coatings

Thermal barrier coatings (TBCs) have been widely used by aero and land based gas turbines to protect hot section parts from oxidation and thermal loads. These coatings are generally consisting of multiple layers of coating (usually two) with each layer having a specific function. TBCs are generally deposited with air plasma spray (APS) or electron beam physical vapor deposition (EB-PVD) techniques. In this paper plasma sprayed TBCs were deposited on to 304 stainless steel substrates then ceramic surfaces were glazing with Nd-YAG laser. Metallographic examinations were applied to the samples to investigate microstructural changes in glazed ceramic layer. Both glazed and as-coated samples were subjected to oxidation tests to measure the high temperature oxidation resistance. The tests showed that, laser glazing is beneficial to oxidation resistance of TBCs. This improvement is attributed to sintering of zirconia layer which act as oxygen barrier and formed during glazing process.

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High Temperature Erosion-Corrosion in Gas Turbines

Volume 5: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; Process Industries; Technology Resources; General ◽

10.1115/82-gt-204 ◽

1982 ◽

Author(s):

J. Stringer

Keyword(s):

High Temperature ◽

Gas Turbines ◽

High Temperature Oxidation ◽

Metal Loss ◽

Protective Oxide ◽

Temperature Oxidation ◽

Oxidation Processes ◽

Erosion Corrosion ◽

Burning Coal ◽

High Temperature Erosion

Under certain circumstances, hot gases containing particulates may be expanded through a turbine. The erosion damage due to the particulates interacts with the high temperature oxidation processes. The interaction may be positive: the oxide layer may be more erosion-resistant than the substrate. The interaction may be negative: the erosion can remove the protective oxide resulting in accelerated metal loss. If the gases contain corrosive materials such as alkali sulfates as well as the particulates, further interactions are possible. These processes are of importance in gas turbine expanders for pressurized fluidized bed combustors burning coal, and several research projects are in progress to study them.

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