Applying Protective Coating on the Turbine Engine Turbine Blades by Means of Plasma Spraying

AbstractThe tendency to increase the temperature of gases and the desire to extend the service life forces the use of a protective coating on the blade. The publication presents the technology of applying a heat-resistant protective coating onto the jet engine turbine blade by means of plasma thermal spraying, taking into account the process of aluminizing and heat treatment after aluminizing. The paper presents the results of work on the possibilities of shaping the thickness of the protective coating on the blade by changing the parameters of the spraying process, such as spraying distance, amount of hydrogen, amount of argon and the number of torch passes.

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Aero Engine Test Experience With CMSX-4® Alloy Single-Crystal Turbine Blades

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2816600 ◽

1996 ◽

Vol 118 (2) ◽

pp. 380-388 ◽

Cited By ~ 25

Author(s):

K. P. L. Fullagar ◽

R. W. Broomfield ◽

M. Hulands ◽

K. Harris ◽

G. L. Erickson ◽

...

Keyword(s):

Heat Treatment ◽

Single Crystal ◽

Turbine Blade ◽

Hot Corrosion ◽

Turbine Blades ◽

Casting Process ◽

Creep Rupture ◽

Coating Performance ◽

Turbine Engine ◽

Mechanical Fatigue

A team approach involving a turbine engine company (Rolls-Royce), its single-crystal casting facilities, and a superalloy developer and ingot manufacturer (Cannon-Muskegon), utilizing the concepts of simultaneous engineering, has been used to develop CMSX-4 alloy successfully for turbine blade applications. CMSX-4 alloy is a second-generation nickel-base single-crystal superalloy containing 3 percent (wt) rhenium (Re) and 70 percent volume fraction of the coherent γ′ precipitate strengthening phase. Its finely balanced composition offers an attractive range of properties for turbine airfoil applications. In particular the alloy’s combination of high strength in relation to creep-rupture, mechanical and thermal fatigue, good phase stability following extensive high temperature, stressed exposure and oxidation, hot corrosion and coating performance, are attractive for turbine engine applications where engine performance and turbine airfoil durability are of prime importance. The paper details the single-crystal casting process and heat treatment manufacturing development for turbine blades in CMSX-4 alloy. Competitive single-crystal casting yields are being achieved in production and extensive vacuum heat treatment experience confirms CMSX-4 alloy to have a practical production solution heat treat/homogenization “window.” The creep-rupture data-base on CMSX-4 alloy now includes 325 data points from 17 heats including 3630 kg (8000 lb) production size heats. An appreciable portion of this data was machined-from-blade (MFB) properties, which indicate turbine blade component capabilities based on single-crystal casting process, component configuration, and heat treatment. The use of hot isostatic pressing (HIP) has been shown to eliminate single-crystal casting micropores, which along with the essential absence of γ/γ′ eutectic phase, carbides, stable oxide, nitride and sulfide inclusions, results in remarkably high mechanical fatigue properties, with smooth and particularly notched specimens. The Re addition has been shown not only to benefit creep and mechanical fatigue strength (with and without HIP), but also bare oxidation, hot corrosion (sulfidation), and coating performance. The high level of balanced properties determined by extensive laboratory evaluation has been confirmed during engine testing of the Rolls-Royce Pegasus turbofan.

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Aero Engine Test Experience With CMSX-4® Alloy Single Crystal Turbine Blades

Volume 2: Aircraft Engine; Marine; Microturbines and Small Turbomachinery ◽

10.1115/94-gt-169 ◽

1994 ◽

Cited By ~ 1

Author(s):

Keith P. L. Fullagar ◽

Robert W. Broomfield ◽

Mark Hulands ◽

Ken Harris ◽

Gary L. Erickson ◽

...

Keyword(s):

Heat Treatment ◽

Single Crystal ◽

Turbine Blade ◽

Hot Corrosion ◽

Turbine Blades ◽

Casting Process ◽

Creep Rupture ◽

Coating Performance ◽

Turbine Engine ◽

Mechanical Fatigue

A team approach involving a turbine engine company [Rolls-Royce], its single crystal casting facilities and a superalloy developer and ingot manufacturer [Cannon-Muskegon], utilizing the concepts of simultaneous engineering, has been used to successfully develop CMSX-4 alloy for turbine blade applications. CMSX-4 alloy is a second generation nickel-base single crystal superalloy containing 3% (wt) rhenium (Re) and 70% volume fraction of the coherent γ′ precipitate strengthening phase. Its finely balanced composition offers an attractive range of properties for turbine airfoil applications. In particular the alloy’s combination of high strength in relation to creep-rupture, mechanical and thermal fatigue, good phase stability following extensive high temperature, stressed exposure and oxidation, hot corrosion and coating performance, are attractive for turbine engine applications where engine performance and turbine airfoil durability are of prime importance. The paper details the single crystal casting process and heat treatment manufacturing development for turbine blades in CMSX-4 alloy. Competitive single crystal casting yields are being achieved in production and extensive vacuum heat treatment experience confirms CMSX-4 alloy to have a practical production solution heat treat / homogenization “window”. The creep-rupture data-base on CMSX-4 alloy now includes 325 data points from seventeen heats including fourteen 3630 kg (8000 lb) production size heats. An appreciable portion of this data was machined-from-blade (MFB) properties which indicate turbine blade component capabilities based on single crystal casting process, component configuration and heat treatment. The use of hot-isostatic-pressing (HIP) has been shown to eliminate single crystal casting micropores which along with the essential absence of γ/γ′ eutectic phase, carbides, stable oxide, nitride and sulphide inclusions results in remarkably high mechanical fatigue properties, with smooth and particularly notched specimens. The Re addition has been shown to not only benefit creep and mechanical fatigue strength (with and without HIP), but also bare oxidation, hot corrosion (sulphidation) and coating performance. The high level of balanced properties determined by extensive laboratory evaluation has been confirmed during engine testing the Rolls-Royce Pegasus turbofan.

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Improvement of Solution Type Plasma Spraying Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.502.505 ◽

2005 ◽

Vol 502 ◽

pp. 505-510 ◽

Cited By ~ 2

Author(s):

Masami Futamata ◽

Xiaohui Gai ◽

Toyokazu Mizumoto ◽

Kimio Nakanishi

Keyword(s):

Mechanical Properties ◽

Plasma Spraying ◽

Hollow Cathode ◽

Thermal History ◽

Thermal Spraying ◽

Physical And Mechanical Properties ◽

Good Reproducibility ◽

Solution Type ◽

Plasma Spraying Process ◽

Spraying Process

To fabricate thermal spraying coatings with good reproducibility, it is necessary to improve the process of the equalization of both thermal history and impacting behavior of the particles. In this study, the characteristics of the solution type plasma spraying using the hollow-cathode type torch are investigated. The physical and mechanical properties that are different from usual thermal spraying coatings are described. By using solutions including metal ingredients in a state of ion, colloid or sol, thinner coating that cannot be made by conventional plasma spraying methods is formed on various substrates. The coatings are uniform in appearance.

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Comprehensive report on Materials for Gas Turbine Engine Components

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b1036.1292s219 ◽

2019 ◽

Vol 9 (2S2) ◽

pp. 155-158

Keyword(s):

Gas Turbine ◽

Turbine Blade ◽

Thermal Stresses ◽

Prolonged Exposure ◽

Raw Materials ◽

Turbine Blades ◽

Gas Turbine Engine ◽

Operating Conditions ◽

Turbine Engine ◽

Engine Component

In the past three decades, it is very challenging for the researchers to design and development a best gas turbine engine component. Engine component has to face different operating conditions at different working environments. Nickel based superalloys are the best material to design turbine components. Inconel 718, Inconel 617, Hastelloy, Monel and Udimet are the common material used for turbine components. Directional solidification is one of the conventional casting routes followed to develop turbine blades. It is also reported that the raw materials are heat treated / age hardened to enrich the desired properties of the material implementation. Accordingly they are highly susceptible to mechanical and thermal stresses while operating. The hot section of the turbine components will experience repeated thermal stress. The halides in the combination of sulfur, chlorides and vanadate are deposited as molten salt on the surface of the turbine blade. On prolonged exposure the surface of the turbine blade starts to peel as an oxide scale. Microscopic images are the supportive results to compare the surface morphology after complete oxidation / corrosion studies. The spectroscopic results are useful to identify the elemental analysis over oxides formed. The predominant oxides observed are NiO, Cr2O3, Fe2O3 and NiCr2O4. These oxides are vulnerable on prolonged exposure and according to PB ratio the passivation are very less. In recent research, the invention on nickel based superalloys turbine blades produced through other advanced manufacturing process is also compared. A summary was made through comparing the conventional material and advanced materials performance of turbine blade material for high temperature performance.

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New Powdered Silicide Materials for Thermal Spraying Process and Coatings on the Niobium Base Alloys

Thermal Spray 1998: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc1998p1167 ◽

1998 ◽

Author(s):

V. Terentieva ◽

O. Bogatchkova ◽

D. Cornu

Keyword(s):

Protective Coating ◽

Protective Coatings ◽

Thermal Spraying ◽

Base Material ◽

Theory And Practice ◽

Powder Materials ◽

Self Healing ◽

High Enthalpy ◽

Boride Phases ◽

Spraying Process

Abstract The given article presents some results of the scientific research devoted to the development of a new class of scale-resistant powder materials of the Si-Ti-Mo-B system for thermal spraying and using these materials for the creation of heat-resistant coatings on the niobium base alloys by means of various methods of thermal spraying. Also under consideration are problems relating to the theory and practice of obtaining reliable protective coatings on high-melting metals and their alloys, niobium ones included, intended for operation in high-enthalpy oxygen-containing gas flows. Hazard in commencing an oxidation reaction of the base material under coating is connected with density of open pores and cracks, and partial pressure of the oxidizer. Powdered multicomponent heterophase materials for gas-thermal spraying of protective coating with a self-healing ability and controlled properties are proposed. Finally the results of some properties of new silicide-type heterophase powders containing silicide and boride phases for a thermal spraying process and some properties of protective coating deposited on the niobium base alloys by means of a thermal spraying technique are presented.

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The Influence of Thermal Treatment upon Nanostructure and Composition of YZrO Based Ceramics Obtained by Atmospheric Plasma Spraying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.837.711 ◽

2013 ◽

Vol 837 ◽

pp. 711-717

Author(s):

Geanina Laura Pintilei ◽

Florin Brânza ◽

Valentin Nica ◽

Sorin Iacob Strugaru ◽

Eduard Sebastian Bârcă ◽

...

Keyword(s):

Thermal Treatment ◽

Plasma Spraying ◽

Turbine Blades ◽

Reference Sample ◽

Atmospheric Plasma Spraying ◽

Atmospheric Plasma ◽

Alloy Sample ◽

Sem Images ◽

Turbine Engine ◽

Barrier Coating

This paper presents a concept of thermal barrier coating used to prevent exfoliation and increase the maximum working temperature of a turbine engine. The coating consist of a ZrO2/20%Y2O3 ceramic layer and a NiCrAlY adherent layer, deposited by atmospheric plasma spraying (APS), on a Ni super alloy sample usually used for the manufacturing of turbine blades. The sample was subjected to thermal treatment and after that analyzed. SEM images of the samples were taken, to analyze their behaviour to thermal treatment. . Reference sample (without thermal treatment) and samples subjected to 5, 10 and 15 hours heat treatment were investigated using X-ray diffraction in 25-130o 2θ interval.

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Coating Stripping Method for Refurbishing of Gas Turbine Blades and Vanes

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award; General ◽

10.1115/99-gt-426 ◽

1999 ◽

Author(s):

Sergio Corcoruto ◽

Umberto Guerreschi ◽

Ettore Gandini

Keyword(s):

Heat Treatment ◽

Gas Turbines ◽

Turbine Blades ◽

Base Material ◽

Vacuum Plasma Spray ◽

Plasma Gun ◽

Stripping Method ◽

Heat Shields ◽

Overlay Coatings ◽

Spraying Process

Hot gas path components (blades, vanes, heat shields...) in modern gas turbines are protected against hot corrosion and oxidation by MCrAlY overlay coatings deposited throughout Vacuum Plasma Spray (VPS) process. These coatings are designed to be consumed during the operation of the engine. To extend the life of the parts the exhausted coatings must be removed without damage to the base material, so already used parts could be reapplied with new coatings and returned to service. A stripping method has been developed in alternative to the acid stripping. The originality of the method is in using a spraying process to deposit onto the MCrAlY coating a layer of aluminium, followed by a diffusion heat treatment in vacuum. The resulting brittle aluminide layer is easily removed by mechanical means, like grit blasting. The aluminium spraying process has been developed for turbine blades and vanes with a plasma gun positioned on a six axis robot, while uncoated areas are stopped off from aluminising. The penetration of aluminium is controlled by proper heat treatment parameters to guarantee uniformity and repeatability. The capability of recoating stripped parts as new ones has been verified.

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Mechanical Properties According to Heat Treatment for Gas Turbine Blade Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.209 ◽

2007 ◽

Vol 26-28 ◽

pp. 209-212

Author(s):

Moon Young Kim ◽

Sung Ho Yang ◽

Kuk Hyun Song

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Gas Turbine ◽

Turbine Blade ◽

Turbine Blades ◽

Hot Isostatic Pressing ◽

Experimental Result ◽

Gas Turbine Blade ◽

Post Heat Treatment ◽

Gas Turbine Blades

This work was studied for the changes of thermal properties on GTD-111 DS (Directional Solidification) gas turbine blade. In this study, gas turbine blades with 24,000~34,000 firing hours was used to get more effective result, gradually applied hot isostatic pressing (HIP) and post-heat treatment for these samples. In the latter steps, we observed changes of γ´ phase affected in material properties, and microhardness test was carried out to evaluate mechanical properties according to changes of γ´ fraction and shape. Experimental result shows, changes of γ´ fraction and shape were affected by HIP and post-heat treatment. And also mechanical properties changes such as micro-hardness related to γ´ phase. In this study, we explained changing transition of microstructure according to γ´ fraction distribution.

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