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

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.

scholarly journals Structure and Selected Properties of Arc Sprayed Coatings Containing In-Situ Fabricated Fe-Al Intermetallic Phases

Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 1059 ◽  
Author(s):  
Tomasz Chmielewski ◽  
Piotr Siwek ◽  
Marcin Chmielewski ◽  
Anna Piątkowska ◽  
Agnieszka Grabias ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Composite Coatings ◽  
Thermal Spraying ◽  
Intermetallic Phases ◽  
Arc Spraying ◽  
Coating Materials ◽  
Two Phases ◽  
Sprayed Coatings ◽  
Spraying Process

The paper presents the results of research on the production by means of arc spraying of composite coatings from the Fe-Al system with participation of in-situ intermetallic phases. The arc spraying process was carried out by simultaneously melting two different electrode wires, aluminum and steel. The aim of the research is to create protective coatings with a composite structure with a significant participation of FexAly as an intermetallic phases reinforcement. The synthesis of intermetallic phases takes place during the (in-situ) spraying process. Currently most coatings involving intermetallic phases are manufactured by different thermal spraying methods using coating materials in the form of prefabricated powders containing intermetallic phases. The obtained results showed the local occurrence of intermetallic phases from the Fe-Al system, and the dominant components of the structure have two phases, aluminum solid solutions in iron and iron in aluminum. The participation of intermetallic phases in the coating is relatively low, but its effect on the properties of the coating material is significant.

scholarly journals Materials for Gas-Thermal Spraying, Obtained by Diffusion Alloying from Powders Based on Austenitic Steels

2019 ◽  
Vol 18 (5) ◽  
pp. 380-385
Author(s):  
F. I. Panteleenko ◽  
V. A. Okovity ◽  
A. F. Panteleenko
Keyword(s):  
Powder Material ◽  
Experimental Studies ◽  
Thermal Spraying ◽  
Thermal Exposure ◽  
Treatment Temperature ◽  
Austenitic Steels ◽  
Alloying Elements ◽  
Powder Materials ◽  
Boride Phase ◽  
Boride Phases

The article presents experimental studies of composite powder materials for plasma spraying, obtained by the method of diffusion doping of powder materials based on austenitic steels. It is indicated that the main factors forming the diffusion layer on a powder material are a composition of the required saturating medium, treatment temperature and duration of chemical and thermal exposure. Creation of single-phase diffusion layers is possible only in the case of a minimum level of temperature-time characteristics during heat treatment. This is also facilitated by the use of media with a low concentration of boron and introduction of additives inhibiting saturation process (such as carbon, aluminum, silicon) into a saturating mixture of powder. Structure and composition of powders have been thoroughly investigated with the help of X-ray microanalysis that has made it possible to study location of elements contributing to powder alloying and micro-durametric characteristics. A component of high-boride phase is increasing due to higher degree of powder material alloying. Significant changes in phase composition, as well as the chemical one, are noticeable in diffusion processing of the following alloyed powder materials: РR-Х18N9, РR-Х18N10, РR-Х18N15. Free carbon being displaced by boride into a transition zone creates dispersed complex carbide compounds with chromium. This is confirmed by distribution nature of carbide-forming components in a powder particle. All carbide-forming elements have characteristic concentration peaks-bursts in contrast to non-carbideforming silicon. Silicon is practically not present in the considered FeB phase and it is found only in a very small amount in the studied Fe2B phase; it is pushed aside by high-boride phases to a sublayer. The change in microhardness of the FeB and Fe2B phases under study is associated with dissolution of corresponding alloying elements in them and distortions of a crystal lattice in borides. A similar phenomenon is also characteristic for saturation while using boron or while making chemical and thermal treatment of alloyed steels, it has been noted in a number of studies. The increase in microhardness of a particle nucleus during its boriding is caused by displacement of carbon and alloying elements by growing front of boride phases. A core zone moves with an increased microhardness to a particle core while increasing temperature mode and time of boronization and up to realization of the effect with counter diffusion.

The Composite Materials for High Erosion Resistance Coatings Applied in Power Industry

2016 ◽  
Vol 246 ◽  
pp. 127-130
Author(s):  
Bożena Szczucka-Lasota ◽  
Krzysztof Szymański ◽  
Jan Piwnik
Keyword(s):  
Composite Materials ◽  
Erosion Resistance ◽  
Protective Coatings ◽  
Thermal Spraying ◽  
Innovative Technology ◽  
Power Plant Boiler ◽  
Corrosion Resistant Coatings ◽  
Spraying Process ◽  
Spraying Method ◽  
Plant Boiler

The article presents the issues related to composite materials and the fabrication process of protective coatings by thermal spraying methods used for the protection of power plant boiler elements . The basic composite materials for thermal spraying process were characterized. The presented materials allow produced the erosion-corrosion resistant coatings. The chemical composition, phase structure and properties of the selected materials are presented. The basic group of coatings with the high corrosion and erosion resistance are produced by thermal spraying method, like HVOF (High velocity oxy fuel). In this article the selected properties of composite materials sprayed by innovative technology are characterized.

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

2020 ◽  
Vol 50 (1) ◽  
pp. 193-213
Author(s):  
Leszek Ułanowicz ◽  
Andrzej Dudziński ◽  
Paweł Szczepaniak ◽  
Mirosław Nowakowski
Keyword(s):  
Heat Treatment ◽  
Service Life ◽  
Plasma Spraying ◽  
Turbine Blade ◽  
Protective Coating ◽  
Turbine Blades ◽  
Thermal Spraying ◽  
Jet Engine ◽  
Turbine Engine ◽  
Spraying Process

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.

Composite cladded powders for spraying of protective coatings

2019 ◽  
pp. 59-64
Author(s):  
E. Yu. Gerashchenkova ◽  
T. I. Bobkova ◽  
E. A. Samodelkin ◽  
B. V. Farmakovsky
Keyword(s):  
Tungsten Carbide ◽  
Gas Phase ◽  
High Speed ◽  
Protective Coatings ◽  
Powder Materials ◽  
Nanosized Particles

The paper presents results of the development of technology for producing cladded and surfacealloyed powder materials. High-speed mechanosynthesis of matrix powders of FeCrAl and solid nanosized particles of tungsten carbide occurs in a disintegrator in the presence of an active gas phase (nitrogen).

Crack Resistance of Weld Seals, Hardening Methods and Composite Tools Quality

2014 ◽  
Vol 682 ◽  
pp. 431-437 ◽  
Author(s):  
V.A. Petrova ◽  
A.A. Bakanov ◽  
A.V. Walter
Keyword(s):  
Crack Resistance ◽  
Interfacial Adhesion ◽  
Thermal Spraying ◽  
Substrate Material ◽  
Metallographic Analysis ◽  
Alternating Projections ◽  
Optical Profilometry ◽  
Surface Optical ◽  
End Products ◽  
Spraying Process

The paper presents a pretreatment of the substrate material prior to the thermal spraying process. The ultrasonic finishing method allowed creation of a rolling topography comprising alternating projections and cavities, compressive stress, and increase of the number of defects on the surface. Optical profilometry and metallographic analysis allowed detecting of adhesion zones which form a strong physicochemical bond at the interface between the coating and the substrate material. This interfacial adhesion should provide a firm adhesion strength in end products.

Assessment of Damage from Organic Protective Coating Treatments to Historic Stone Buildings and Sculptures

2010 ◽  
Vol 44-47 ◽  
pp. 610-613
Author(s):  
Qiang Liu ◽  
Bing Jian Zhang
Keyword(s):  
Protective Coating ◽  
Side Effect ◽  
Protective Coatings ◽  
Organic Coating ◽  
Stone Conservation ◽  
Silicon Compounds ◽  
Artificial Weathering ◽  
Organic Silicon ◽  
Destruction Mechanism ◽  
Historic Stone

The conservation of historic stone buildings and sculptures is receiving growing attention because of weathering. Now, the techniques for stone conservation are primarily achieved through the use of organic coating treatments. Although some defects of organic protective materials have been recognized, the further shortcoming is still short of awareness. Here we show our investigations of the side effect of organic coating treatments. Some kinds of common stones, including sandstone, tuff, granite, dolomite and marble, were selected as protected objects. Organic silicon compounds were used as protective coatings. The artificial weathering, including salting, freezing and heating, was designed. The treated stones’ decaying was investigated. The results reveal that the treated stone decaying is aggravated. Moreover, the destruction mechanism has been discussed.

Improvement of Solution Type Plasma Spraying Process

2005 ◽  
Vol 502 ◽  
pp. 505-510 ◽  
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.

scholarly journals Self-healing corrosion protective coatings based on micro/nanocarriers: A review

2021 ◽  
Author(s):  
Tong Liu ◽  
Lingwei Ma ◽  
Xin Wang ◽  
Jinke Wang ◽  
Hongchang Qian ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Self Healing

Effects of Gun Nozzle Geometry on High Velocity Oxygen-Fuel (HVOF) Thermal Spraying Process

1998 ◽  
Author(s):  
K. Sakaki ◽  
Y. Shimizu ◽  
Y. Gouda ◽  
A. Devasenapathi
Keyword(s):  
Numerical Simulation ◽  
Experimental Studies ◽  
Thermal Spraying ◽  
Deposition Efficiency ◽  
Divergence Angle ◽  
Nozzle Geometry ◽  
Oxide Content ◽  
Hvof Thermal Spraying ◽  
Throat Diameter ◽  
Spraying Process

Abstract Effect of nozzle geometry (such as throat diameter of a barrel nozzle, exit diameter and exit divergence angle of a divergent nozzle) on HVOF thermal spraying process (thermodynamical behavior of combustion gas and spray particles) was investigated by numerical simulation and experiments with Jet KoteTM II system. The process changes inside the nozzle as obtained by numerical simulation studies were related to the coating properties. A NiCrAIY alloy powder was used for the experimental studies. While the throat diameter of the barrel nozzle was found to have only a slight effect on the microstructure, hardness, oxygen content and deposition efficiency of the coatings, the change in divergent section length (rather than exit diameter and exit divergence angle) had a significant effect. With increase in divergent section length of the nozzle, the amount of oxide content of the NiCrAIY coatings decreased and the deposition efficiency increased significantly. Also, with increase in the exit diameter of the divergent nozzle, the gas temperature and the degree of melting of the particle decreased. On the other hand the calculated particle velocity showed a slight increase while the gas velocity increased significantly.

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