A Combined Brazing and Aluminizing Process for Repairing Turbine Blades by Thermal Spraying Using the Coating System NiCrSi/NiCoCrAlY/Al

Nicolaus, Martin; Möhwald, Kai; Maier, Hans Jürgen

doi:10.1007/s11666-017-0612-z

Cited by 12 publications

(10 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The purpose of repair is to return the component to its original condition, "like new," or "almost new" [48]. The standard process used to repair gas-turbine components are heat treatment, welding, brazing, and recoating [49].…”

Section: Relation Of Wear To the Hot-gas-path Components Of Gas Turbinesmentioning

confidence: 99%

Wear Characteristics of Superalloy and Hardface Coatings in Gas Turbine Applications–A Review

Pauzi

Ghazali

Zamri

et al. 2020

Metals

View full text Add to dashboard Cite

In the gas-turbine research field, superalloys are some of the most widely used materials as they offer excellent strength, particularly at extreme temperatures. Vital components such as combustion liners, transition pieces, blades, and vanes, which are often severely affected by wear, have been identified. These critical components are exposed to very high temperatures (ranging from 570 to 1300 °C) in hot-gas-path systems and are generally subjected to heavy repair processes for maintenance works. Major degradation such as abrasive wear and fretting fatigue wear are predominant mechanisms in combustion liners and transition pieces during start–stop or peaking operation, resulting in high cost if inadequately protected. Another type of wear-like erosion is also prominent in turbine blades and vanes. Nimonic 263, Hastelloy X, and GTD 111 are examples of superalloys used in the gas-turbine industry. This review covers the development of hardface coatings used to protect the surfaces of components from wear and erosion. The application of hardface coatings helps reduce friction and wear, which can increase the lifespan of materials. Moreover, chromium carbide and Stellite 6 hardface coatings are widely used for hot-section components in gas turbines because they offer excellent resistance against wear and erosion. The effectiveness of these coatings to mitigate wear and increase the performance is further investigated. We also discuss in detail the current developments in combining these coating with other hard particles to improve wear resistance. The principles of this coating development can be extended to other high-temperature applications in the power-generation industry.

show abstract

Section: Relation Of Wear To the Hot-gas-path Components Of Gas Turbinesmentioning

confidence: 99%

Wear Characteristics of Superalloy and Hardface Coatings in Gas Turbine Applications–A Review

Pauzi

Ghazali

Zamri

et al. 2020

Metals

View full text Add to dashboard Cite

show abstract

“…They found an isothermal solidified gap of approximately 1000 µm with a six-hour treatment. Nicolaus et al [3][4][5] developed a hybrid process for repairing high-pressure turbine blades.…”

Section: Base Alloy Alloys Filler Metal Thickness Brazing Microstrucmentioning

confidence: 99%

“…Because of its versatility, BNi-9 (MBF 80, Nicobraz 150) has been extensively studied in base Ni alloys, base Co alloys and stainless steel. This filler material can be applied as either a foil or paste, each one having a specific application; an amorphous foil provides more uniform joints assemblies [1], and powders mixed with a binder and paste are used to repair cracks and wear defects [2][3][4][5][6][7]. In Table 1, the experimental conditions of some of these studies have been summarized.…”

Section: Introductionmentioning

confidence: 99%

Metallurgical Interaction among BNi-9 and Waspaloy, FSX-414 or 304-Type Stainless Steel under TLP Cycle

Flores-Escareño

Castro‐Román

Hernández-García³

et al. 2020

Metals

View full text Add to dashboard Cite

The metallurgical interaction of BNi-9 filler metal paste with Waspaloy, Ni-coated Waspaloy, FSX-414, and 304-SS is studied in a brazing treatment under an argon atmosphere with an isothermal hold for one hour at 1150 °C. The Waspaloy alloys were brazed under both solubilized and aging conditions. Before brazing, some Waspaloy samples were electrochemically coated with an Ni layer 35-40 μm thick. The microstructures of the FSX-414 and 304-SS alloys showed that the thickness of the isothermal solidification zones was approximately 50 μm, while this thickness was not well defined in the Waspaloy samples. The Ni-coated solubilized Waspaloy showed a wider diffusive zone, which was associated with an increase in the penetration extension of the liquid films. The analysis of grain orientation in all brazed zones of the Waspaloy samples showed aleatory characteristics. Plastic factors in the different brazed zones were also obtained by nanoindentation under 350 mN loads. It was observed that the plastic factor was low when the width of the diffusive zone increased. The plastic factor in the Ni-coated Waspaloy was the lowest, while the diffusive zone in this sample had the largest width. The BNi-9 wettability is better in FSX-414, and 304-SS than in Waspaloy. Ni coating in Waspaloy improves BNi-9 wettability.

show abstract

“…Corrosion current of coated sample was observed to be lower even though corrosion current of uncoated sample was extremely high. As a result, it could be asserted that corrosion resistance of coated material increased and the current decreased (Nicolaus et al, 2017).…”

Section: Edax Analysis Of Samples Of Exhaust Pipesmentioning

confidence: 99%

Investigation of the Effect of Cr3C2 Coating by Plasma Spray Process on Exhaust Pipe of a Diesel Engine

Şap

Hazar

Şap

2020

Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi

View full text Add to dashboard Cite

Lifetime of exhaust system decreases rapidly under negative factors such as high exhaust gas temperature, chemical solvents in exhaust gas, water vapor, water in rainy weather, mud, salt poured on the roads to prevent frosting in winter months, etc. Exhaust system of internal combustion engines need to be replaced after a while based on regions and conditions in which they are used. In this study, outer parts of exhaust pipe of a diesel engine were coated with 100-micron-thick chromium carbide (Cr3C2) material by using plasma spray method. The effect of chemical and physical solvent and deforming factors that affect externally was examined by coating exhaust pipe with chromium carbide (Cr3C2) material. As a result of experiments, it was determined that corrosion resistance increased by 85%. According to scanning electron microscope (SEM), micro hardness, EDAX, and X-RD analyses, the coating was observed to generate a uniform structure on substrate material. Thus, it could be concluded that factors decreasing the lifetime of exhaust system were met by coating material, the surface structure enhanced, and material lifetime increased compared to standard exhaust pipe.

show abstract

A Combined Brazing and Aluminizing Process for Repairing Turbine Blades by Thermal Spraying Using the Coating System NiCrSi/NiCoCrAlY/Al

Cited by 12 publications

References 22 publications

Wear Characteristics of Superalloy and Hardface Coatings in Gas Turbine Applications–A Review

Wear Characteristics of Superalloy and Hardface Coatings in Gas Turbine Applications–A Review

Metallurgical Interaction among BNi-9 and Waspaloy, FSX-414 or 304-Type Stainless Steel under TLP Cycle

Investigation of the Effect of Cr3C2 Coating by Plasma Spray Process on Exhaust Pipe of a Diesel Engine

Contact Info

Product

Resources

About