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The plasma sprayed bronze coatings are widely used for repairing of plain bearing used in different applications. This type of coating was not deeply analyzed in state-of-art publications. In presented article we fill this gap in the case of plasma spraying process. The influence of power current (300/500/700A) and hydrogen flow (0/4/8 NLPM) on microstructure and thickness of aluminium bronze-polyester coating was investigated. The Thermico A60 plasma torch was used for thermal spray process of coating on flat carbon steel samples (grade S355). The Metco 604NS was sprayed with 20g/min powder feed rate. The obtained results showed the presence of local large pores formed by burning of polyester in plasma plume. This gap makes role of oil pockets in bearings. The obtained coatings were characterized by large deviation in thickness in range 200-350 micrometers. It might be concluded that in requires additional milling process after deposition.

In the article the microstructure and phase composition of boride coatings deposited on selected structural steels were investigated. The boride coatings were produced using pack cementation method using commercial EKABOR-2 mixture containing of 50 wt. % of new and 50 wt. % of used powder. Boride coatings were deposited on alloyed structural steels grades (PN/EN 10084 standard): 16MnCr5, 18CrNiMo7-6, 41CrAlMo7 42CrMo4. Cylindrical samples with a diameter of 30 mm and a height of 30 mm were boronized in powder at 1000°C for 2, 4 and 6 hours in an argon atmosphere. The process was carried out in an industrial CVD Bernex BPX 325S device. The microstructure was analyzed using scanning electron microscope Phenom XL equipped with EDS spectrometer. The XRD phase analysis was conducted using XTRa diffractometer (ARL). The thickness as well as phase composition was analyzed on coatings formed on each grades of steels. The most of obtained boride coatings were characterized by single-phase structure (Fe2B). The formation of brittle FeB phase was detected only on 16MnCr5 steel grades steels.

This study investigates the optimal conditions to deposit a thermal barrier coating using micro- and nanopowders in the air plasma spraying (APS) process. The influence of the APS process parameters on the thickness, porosity and hardness of the yttria-stabilized zirconia (YSZ; ZrO2× 8Y2O3) coatings deposited with a single-electrode plasma gun was determined. The temperature and velocity of melted particles were determined by the DPV diagnostic system to decrease the number of experimental processes. The current and H2flow rate were changed in this research. Metco-6700 YSZ micropowder has already been used in plasma spray physical vapor deposition. The results of this study suggest the possibility of using it for APS. The particles of this powder are characterized by high temperature (2,700°C–2,900°C) and high speed (>380 m/s). The highest thickness of the coating was obtained with 6 NLPM (normal liter per minute) H2flow and 800 A current. Difficulties were observed with the feeding of the powder particles at higher H2flow. The results showed that using APS, deposition of Metco-6609, a nanopowder normally used in suspension plasma spraying, is possible. In this research, this powder was fed using a carrier gas. The coatings were around 40 μm thick and had high porosity. The lowest porosity of the coating was obtained at a current of 600 A and H2flow rate of 12 NLPM. In the coatings, unmelted spherical particles were also visible.

Plasma Spray Physical Vapour Deposition (PS-PVD) is one of the promising methods considered as an alternative to Electron Beam Physical Vapour Deposition (EB-PVD) process used for production of ceramic columnar layer for turbine blades protection against high temperature. The PS-PVD method enables to control the coating structure. In presented article the dense to columnar structure was formed during single-step PS-PVD process using yttria stabilized zirconia oxide (YSZ). The ceramic coating was deposited using LPPS-Hybrid (Oerlikon-Metco) system at Rzeszow University of Technology. The IN 713 alloy with aluminide coating produced by CVD method was used as a base material. The inner zone of the ceramic coating was characterized by dense structure and the outer was characterized by columnar structure. The influence of power current, gas composition flow, powder feed rate and coating time on thickness of both zones was investigated using Scanning Electron Microscopy method. The relationship between process parameters and thermal conductivity was also investigated using Laser Flash Method (LFA). Conducted experimental process showed that using of 1800A power current higher Ar flow (80 NLPM) as well as powder feed rate (30 g/min) enables to obtain dense structure of coating. When higher energy of plasma (power current 2200 A, plasma gasses flow (Ar-35 NLPM, He-60 NLPM) and lower powder feed rate was used the columnar zone was formed. The thickness of obtained coating was in range 140-200 μm. The formation of thick dense layer increased the overall thermal conductivity of coating in comparison with conventional columnar ceramic layer. The combination of thin 20 μm dense-zone with thick (120 μm) columnar zone reduces thermal conductivity of whole coating.

The MCrAlY overlay coatings are widely used for high-temperature protection of hot section part of gas turbines and jet engines. This type of coatings are usually thermally sprayed using APS (Atmospheric Plasma Spraying), LPPS (Low Pressure Plasma Spraying) as well as HVOF (High Velocity Oxygen Fuel) methods. In present article the newly developed ethanol based HVOF gun was used for production of this type of coatings. The stainless steel 18-8 type was used as a base material. The AMDRY 386 (Oerlikon-Metco) NiCrAlY powder was used for coatings production. In the research different oxygen (400, 500, 600 NLPM) and ethanol (16.5, 18.3, 21.3, 23.6 and 26.6 dm3/h) flow ratio were selected for experimental processes. The powder feed ratio was also changed during process. After deposition the microstructural assessment using Scanning Electron Microscopy and chemical composition analysis using EDS method were conducted. The obtained results showed that coating was above 100 μm thick depending on the process parameters. The low concentration of pores and oxides was also observed on coatings cross-section. Using of ethanol HVOF gun enables to form good quality MCrAlY coatings with 50% reduction of oxygen consumption in comparison with conventional HP/HVOF torch using kerosene such as JP 5000. The other benefit of its using is lower CO2 emission and lower concentration of carbon in coating in comparison with classic JP 5000 HVOF gun. The ethanol HVOF is a promising technology and might be considered as an replacement of LPPS and HVOF process for production of MCrAlY type of coatings.

TiAl intermetallics can be considered an alternative for conventional nickel superalloys in the high-temperature application. A TBC (Thermal Barrier Coatings) with ceramic topcoat with columnar structure obtained using EB-PVD (electron beam physical vapour deposition) is currently used to protect TiAl intermetallics. This article presents the new concept and technology of TBC for TiAl intermetallic alloys. Bond coats produced using the slurry method were obtained. Si and Al nanopowders (70 nm) were used for water-based slurry preparation with different composition of solid fraction: 100 wt.% of Al, 50 wt.% Al + 50 wt.% Si and pure Si. Samples of TNM-B1 (TiAl-Nb-Mo) TiAl intermetallic alloy were used as a base material. The samples were immersed in slurries and dried. The samples were heat treated in Ar atmosphere at 1000 °C for 4 h. The outer ceramic layer was produced using the new plasma spray physical vapour deposition (PS-PVD) method. The approximately 110 μm thick outer ceramic layers contained yttria-stabilised zirconium oxide. It was characterised by a columnar structure. Differences in phase composition and structures were observed in bond coats. The coatings obtained from Al-contained slurry were approximately 30 μm thick and consisted of two zones: the outer contained the TiAl3 phase and the inner zone consisted of the TiAl2 phase. The second bond coat produced from 50 wt.% Al + 50 wt.% Si slurry was characterised by a similar thickness and contained the TiAl2 phase, as well as titanium silicides. The bond coat formed from pure-Si slurry had a thickness < 10 μm and contained up to 20 at % of Si. This suggests the formation of different types of titanium silicides and Ti-Al phases. The obtained results showed that PS-PVD method can be considered as an alternative to the EB-PVD method, which is currently applied for deposition a columnar structure ceramic layer. On the other hand, the use of nanopowder for slurry production is problematic due to the smaller thickness of the produced coating in comparison with conventional micro-sized slurries.

Plasma Spray Physical Vapour Deposition (PS-PVD) method was designed for production of ceramic layer on nickel superalloys. In typical process before deposition the base material is heated by plasma up to 900 °C. In present article the yttria stabilized zirconia (YSZ) was deposited on low melting point materials: 2017A-type aluminium alloy and Cu-ETP copper. The influence of power current, process time and powder feed rate on structure and thickness of obtained coatings was analysed. During first deposition process the overheating of Al-sample was observed and as result the power current was decreased to 1600 A. In the next experimental the approx. 5 mm thick dense coating was formed. During experimental processes of YSZ deposition on copper the thickness of coating increased from approx. 5 to 22 mm. The copper-oxide layer was formed under ceramic layer. The microscopic assessment showed the difficulties in formation of columnar ceramic layer on use base materials. The obtained coating was characterized by dense structure as a result of lower plasma energy during process. The increasing of power current is not possible in the case of overheating of base material.

The boride coatings are characterized by attractive set of properties: high wear resistance and good high-temperature corrosion. In present research the diffusion boride coatings were obtained on X39CrMo17-1 stainless steel. The pack-boriding process was conducted using commercial Ekabor 2 powder. The influence of time of process on thickness and chemical composition was analysed. The boriding process was conducted in 2, 4, 6 hours at 1000 °C using retort furnace. The obtained coating was characterized by double layer structure and contained the FeB in outer layer and Fe2B in inner layer. The thickness of boride coatings increased with process time. The analysis of obtained results showed that the optimal thickness of coating was obtained during 4-h pack boriding.

Thermal barrier coatings are widely used for protection of gas turbine parts against high temperature oxidation and hot corrosion. In present work the microstructural assessment of TBCs produced by atmospheric plasma spray (APS) method was conducted. Three types of ceramic powders were used: magnesia- stabilized zirconia oxide (Metco 210), yttria stabilized zirconia oxide (YSZ -Metco 204) and fine-grained YSZ – Metco 6700. As a base material the Inconel 713 was used as well and CoNiCrAlY was plasma sprayed (APS) as a bond coat. The thickness of all ceramic layers was in range 80 – 110 μm. The elemental mapping of cross-section of magnesia-stabilized zirconia showed the presence of Mg, Zr and O in outer layer. In the YSZ ceramic layer the Y, Zr and O were observed during elemental mapping. The isothermal oxidation test was conducted at 1100 °C for 500 h in static laboratory air. On all samples the delamination and spallation of ceramic layers was observed. Chemical composition analysis of coatings showed the presence of two areas: the first one contained elements from bond coats: Ni, Cr, Al, Co and second area contained O, Cr Co and O that suggest the scale formation. The obtained results showed the total degradation of all ceramic layers as a result of internal stresses in bond-coat. Microscopic analysis showed the areas with complete degradation of bond coats and formation of thick oxides layer.

The nitriding process is a well-known technology for increasing of wear resistance of steel. The conventional gas nitriding process of stainless steel is difficult in the case of surface passivation and formation of Cr2O3. The using of plasma enables to form hard surface area during the nitriding process. The plasma nitriding process was developed using Ionit Metaplas device. The kinetic growth was analysed in 2, 4, 6 and 8 h processes. The plasma gasses composition was selected for formation only diffusion layer without “white area” of nitrides. The microstructure, chemical and phase composition were analysed. As a result, the diffusion layer was formed. The iron nitrides formed the precipitations in the diffusion layer. The obtained results showed that 4h process enables to form nitride layer with required composition and hardness. The relationship between process time and nitride layer thickness and its hardness was observed.

In the article first tests of production of YSZ ceramic coatings using PS-PVD method on graphite were presented. The influence of hydrogen addition on structure and morphology of columns was analyzed. It was shown that width of the columns increased with the increase of hydrogen content in the plasma. The presence of re-solidified oxide vapors between ceramic columns was observed. The obtained results showed the possibility of using of YSZ ceramic layer as a protective layer for metallurgical applications.

Thermal barrier coatings (TBCs) are widely used for protection of gas turbine parts from high temperature and corrosion. In the present study, the new concept of TBCs with three-element-modified aluminide coatings was presented. In the first stage, the Pt and Pd were electroplated on MAR M247 nickel superalloy. In the next stage, the low-activity CVD aluminizing process with Zr or Hf doping was conducted. The ceramic layer containing yttria-stabilized zirconia was obtained by the plasma spray physical vapour deposition (PS-PVD) method. The microscopic examination showed the formation of aluminide coating containing up to 5 at% of Pt and 10 at% of Pd in (Ni, Pt, Pd)Al solid solution. The small concentration of Hf and Zr in diffusion zone of aluminide bond coat was noted as well. The outer ceramic layer was characterized by columnar structure typically formed during the PS-PVD process. The obtained results showed that the new concept of TBCs formed using new processes might be an attractive alternative to conventional coatings produced using the expensive electron beam physical vapour deposition (EB-PVD) method.

The plasma spraying is commonly used in medical application. The Atmospheric Plasma Spray (APS) method was applied for production of yttria-stabilized zirconia (YSZ) on AISI 316L stainless steel surface and also on Ti6Al4V titanium alloy surface. In present article two examples of coatings production were presented. In first experimental the YSZ was plasma sprayed (APS) on 316L stainless steel surface. The coating was deposited using A60 (Thermico) plasma torch. The initial parameters were selected and it was concluded that minimal power current was 500A. The thickness of obtained coating was in range 100-150 micrometers. The X-ray phase analysis showed the presence of tetragonal t-phase of ZrO2. The lamellar structure of coatings with large porosity was observed. In second experimental the newly developed Plasma Spray Physical Vapor Deposition method (PS-PVD) was used. The YSZ coating was deposited on titanium Grade 5 surface. The conducted research showed the formation of two types of coatings structure. When the power current was lower (2000 A) the dense lamellar-like coatings was obtained. If the power current was increased (up to 2200A) the columnar ceramic coating was observed.

The molybdenum is one of the most important refractory metals used in aerospace industry. The main disadvantage of Mo is low oxidation resistance at elevated temperature and the using of protective coatings is necessary. In present article the new types of protective coatings produced by slurry method were developed. The slurries contained Al nanopowder and Si powder as well as non-organic binder (H2CrO4 and water). After immersion and drying the samples with slurries were heat treated at 1000°C in Ar atmosphere. The thickness of obtained coatings was in range 10-20 μm. The presences of phases form Mo-Al as well Mo-Si systems was analyzed using scanning electron microscopy. The developed coatings were used as a bond coat for ceramic layer produced by plasma spray physical vapour deposition method (PS-PVD). In this process the columnar ceramic layer contains yttria stabilized zirconia (YSZ) was obtained wit thickness above 100 μm. The obtained results showed that it is possible to obtain TBC coating on molybdenum contained Al-Si bond coat and outer YSZ ceramic layer. The proposed coating can be used in aerospace applications.

The thermal barrier coatings (TBC) are commonly used for protection of jet engine parts. In presented article the influence of chemical composition of TBCs bond coats on isothermal oxidation resistance was analysed. The bond coat was plasma sprayed (APS) using different MCrAlY alloys produced by Oerlikon-Metco: Metco 4451, AMDRY 997, AMDRY 962, AMDRY 365-1, AMDRY 995C. The conducted research showed big difference in coating thickness despite the same spraying parameters. The difference in porosity was not observed. The isothermal oxidation test was conducted during 500h at 1100°C in static laboratory air. The obtained results showed, that degradation mechanism of MCrAlY bond coats regardless of chemical composition is similar. The formation of scale contained aluminium and chromium oxides was observed. The internal oxidation effect was also observed in produced coatings.

The aim of this study was to examine the possibility of application in APS process Yttria Stabilized Zirconia (YSZ) – Metco 6700 ceramic powder normally used in Low Pressure Plasma Spraying (LPPS) method. Powder grain size is around 10 µm. Parameters such as chemical composition of plasma gases and current were changed to obtain the best result. The experiment was divided into two stages. Firstly, temperature, velocity and size of a molten particle of ceramic powder inside plasma plume were measured via DPV eVolution equipment (TECNAR company) during a different set of process parameters. Plasma plume was also scanned to obtain cross-section contour plots of mentioned properties of the molten particle. Secondly, the same processes were repeated to deposit TBC coatings onto sheet metal to examine the structure.The obtained results showed that it is possible to use fine-grain YSZ powder Metco 6700 for APS process. Obtained ceramic coatings had a thickness from 100 to 240 µm. The plasma sprayed coating was characterised by a smooth surface. The measurement of spraying parameters showed the uniform temperature, velocity and particle size of the powder inside plasma plume.

Thermal Barrier Coatings (TBC) is the most advanced system for protection of turbine blades and vanes against high temperature, and oxidation. They are used in most advanced jet engines. In present article the new Plasma Spray Physical Vapour Deposition Technology was used to obtain yttria stabilized zirconia oxide coating with columnar structure. In research the different process parameters were changed. It was observed that powder feed rate had big influence on coating thickness. The large amount of Ar in plasma gasses combined with high powder feed rate resulted in partial evaporation of ceramic powder and splat-type structure. The same effect was observed when the power current was decreased form 2400 to 1600 A as well as pressure was increased to 200 Pa when the powder feed rate was 30 g/min. The obtained results showed that full evaporation of ceramic powder requires very low feed rate of ceramic material (2 g/min), high power current and high He content into plasma.

In the paper the formation of Thermally Grown Oxides on newly developed Thermal Barrier Coatings were described. The CMSX-4 Single Crystal nickel superalloy was used as a base material. The bondcoat was produced by overaluminizing of an MeCrAlY–type coating deposited by low pressure plasma spraying method (LPPS). The outer ceramic layer of yttria oxide stabilized zirconia oxide (Metco 6700) was deposited by plasma spray physical vapour deposition (PS-PVD). The isothermal oxidation test at 1100oC for 1000h shown that thickness of the TGO layer in overaluminized bondcoat was significantly thicker in comparison with conventional LPPS-sprayed MeCrAlY bondcoats in the same type of TBCs.

The paper presents results of microstructural analysis of Hf-modified aluminide coatings. The coating was obtained using chemical vapour deposition (CVD) method at 1040°C using BPX-Pro 325 S equipment (Iond Bond). The deposition process time was 960 mintutes. The IN-718, IN-100 as well as CMSX-4 single-crystal nickel superalloys were the substrate material. The observation of coating was carried out using scanning electron microscopy. Chemical composition was analyzed using EDS method. The results showed that hafnium accumulates mainly on diffusion/additive layer interface and forms a „chain” of small precipitations. Hafnium was found in the additive NiAl layer of aluminide coating deposited on IN-100 superalloy. Its amount did not exceed 0.3 at %.

The PS-PVD method is a promising technique for production of ceramic coatings from the vapor phase on gas turbine components. The resulting layers combine benefits of coatings made by the plasma spray method and other methods of Physical Vapor Deposition. The plasma spray process is carried out under reduced pressure (~ 200 Pa) and with the use of a gun applied in the method (the LPPS torch 0C3P). The PS-PVD enjoys many of the benefits of plasma spray methods combined with relatively low production costs and overall better properties. One of the significant costs of coating manufacturing by this method is the use of helium as process gas to generate plasma. The authors attempted to form a ceramic coating from ZrO2, where a mixture of argon and nitrogen in various proportions was used. The resulting layers were analyzed by XRD, LFA, SEM-EDS.

In present article the influence of Low Pressure Plasma Spraying (LPPS) process parameters on microstructure of MCrAlY coatings was studied. Nowadays the Atmospheric Plasma Spray (APS) is the most widely used process to obtain MCrAlY-type coatings. The LPPS process may be consider as an alternative technology for deposition of this type coatings which have less porosity and smaller amount of oxides compared to APS coatings. This features are important to obtain coatings with better hot corrosion and oxidation resistance. In order to determine and optimize the process parameters the microscopic investigations were carried out. Assessment of microstructure, thickness of coating and porosity level was conducted as well. Correlation between LPPS parameters and obtained microstructure have been found. It has significant meaning for deposition of MCrAlY coatings which could be applied as a bond coat in thermal barrier coating (TBC).

New refining technology of soda-calcium-silicon glass surfaces with inorganic compounds nano-molecules has been presented in the study. In order to determine modification of the glass surface SEM observation and EDX analysis have been carried out. The UV-VIS, photo-elasticity and ellipsometry examinations were carried out on glass samples. The results of investigations that have been conducted show that refining process of the glass surface by use of nanopowder inorganic compounds deposited electrostatically on glass surface provides forming of very thin (about 50 nm) surface layers [1]. This method of surface modification improves physical and chemical glass properties. In this paper results of microhardness test of refined glass were also presented.

The paper presents a proposed application of the Gunt ET794 turbine model and subsequent tests carried out in order to determine its usability in sample testing under erosive and corrosive conditions. The most important parameter measured during the tests was temperature before the T3 turbine as well as fuel consumption (propane-butane). Following measurement taking and determining conditions, an optimum place for sample attaching was established. CATIA and Autocad software was used to elaborate the sample attachment model. It has been assumed that the tested sample had 14mm in diameter and thickness of 4mm, while the protective coat will be 500μm max. The summary presents additional research and works, whose aim would be to improve the application of the Gunt ET794 as the test stand.

The oxides in the case of theirs properties are important materials for industrial application especially, in aircraft industry for application as thermal barrier coatings. Thermal properties of zirconium oxide stabilized by yttria are better than other ceramic materials. This powder could be stabilized in room temperature by addition of rare earth elements. In this article the thermal analyses of yttria stabilized zirconia (YSZ) oxide are presented as a baseline for future measurements of thermal properties of YSZ powder with addition of rare earth elements. The thermal expansion, specific heat, thermal diffusivity and thermal conductivity of commercially available Matco 6700 powder offered by Sulzer Metco company were analyzed by thermal methods.

The role of thermal barrier coatings is to ensure heat resistance of elements in the hot section of turbofan aircraft engines in high temperatures. Stages of the production process are made up of preparing the base material, forming the aluminide interlayer by chemical vapour deposition method and depositing of the ceramic coating. The paper presents results of tests into microstructure of ZrO2 and Y2O3 ceramic coatings formed by EB-PVD method. The microstructure was assessed in several spots of the turbine blade of a high pressure turbofan engine by means of determining the coating thickness as well as height and width of ceramic columns, depending on the forming conditions.

The paper presents an advanced technology of Thermal Barrier Coatings (TBCs) deposition called Plasma Spray – Physical Vapor Deposition (PS-PVD). The PS-PVD is a low pressure plasma spray technology to deposit coatings out of vapor phase, which enables obtaining of columnar ceramic coatings. In this paper, the influence of various gas mixtures on properties of deposited coatings has been investigated. The measurement of coating thickness was conducted by a light microscopy method, followed by a statistical analysis. All processes had been conducted at a very low feed rate, which additionally affected ceramic microstructure.

High velocity air fuel (HVAF) is one of the high velocity flame spraying process (HVFS). The HVAF method employs a combination of liquid fuel mixed in a chamber with compressed air to obtain high velocity flows. This technology can provide high deposition levels, adequate bond strength as well as high dense coating structure. The working principle of Plasma Spray – Physical Vapor Deposition (PS-PVD) is based on evaporation of the ceramic powder, which enables advanced microstructure of the deposits. In this paper, microstructure of Thermal Barrier Coating (TBC) deposited by HVAF and PS-PVD method was described.

The paper presents results of research into the aluminizing process of TiAl intermetallics. The substrate was Ti48Al2Cr2Nb intermetallic alloy. The BPX Pro 325S CVD system was used for aluminizing process. Used in the experimental were four types of activators: AlCl3, AlF3, ZrCl4 and HfCl4. During the aluminizing process 2 kg of Al-Cr granules were put in a container. The deposition process was carried out in argon atmosphere for a duration of 4 hours at the temperature of 1000°C. The XRD and chemical analysis were conducted. The results showed than aluminide coatings contained TiAl2 and TiAl2 phases were formed using an AlF3 activator. In other processes the amount of Al in the coatings was smaller than in the substrate. The obtained results showed that for the aluminizing process use of aluminum fluorides is necessary.

The paper presents results of research into thermal barrier coatings characterized by high oxidation resistance and hot corrosion. Bondcoats were formed by overaluminizing of an MeCrAlY–type coating deposited by low pressure plasma spraying. The outer ceramic layer of yttrium oxide stabilized zirconia oxide (Metco 6700) was deposited by plasma spray physical vapour deposition (PS-PVD). For comparison purposes additionally LPPS-sprayed were MeCrAlY bondcoats, which were not subsequently aluminized. Used as base material was Rene 80 nickel superalloy. The research has shown that as a result of aluminizing by the CVD method there was formed in the bondcoat a deposit zone built of the β-NiAl phase which protects from oxidation. Preserved below increased chromium content ensures resistance to hot corrosion. The outer ceramic layer was characterized by columnar structure similar to that obtained in the EB-PVD process.

The paper presents results of tests into heat resistance and specific heat capacity of nickel-based superalloys: Rene 80, Mar-M-200+Hf i Mar-M-247+Hf. Heat resistance tests were carried out with the use of a cyclic method. Each cycle involved a 23-hour period of heating at 1100oC, followed by 1-hour air cooling. The DSC method was applied to determine specific heat. Scale microstructure was examined with the use of an electrone microscope. The tested alloys have been proven to enjoy relatively good resistance to corrosion. The Mar-M-200+Hf alloy enjoys the highest specific heat capacity, while the lowest value of specific heat has been recorded for the Mar-M-247+Hf alloy.

The paper presents results of research into isothermal oxidation test of thermal barrier coatings characterized by high oxidation resistance and hot corrosion. Bondcoats were deposited by overaluminizing of MeCrAlY–type coating deposited by LPPS method. The outer ceramic layer of yttrium oxide stabilized zirconia oxide (Metco 6700) was deposited by plasma spray physical vapour deposition (PS-PVD). For comparison purposes additionally LPPS-sprayed were MeCrAlY bondcoats, which were not subsequently aluminized.. The isothermal oxidation test at 1100oC for 1000h shown that thickness of the TGO layer in overaluminized bondcoat was significantly thicker in comparison with conventional LPPS-sprayed MeCrAlY bondcoats.

The carbide coatings are widely used for wear and erosion protection of different materials. In present paper the WC/Co coatings were deposited by a single-cathode Sulzer Metco F-4 plasma gun. The microstructure and thickness measurements were conducted. The erosion test was conducted using a Koechler Air Jet Errosion tester at the temperature of up to 500oC. The procedure was similar to ASTM G76 standard. Changes in erosion resistance of coating into different temperature were observed.

The paper presents the comparison of the structures of the zirconium modified aluminide coatings deposited on pure nickel by the CVD and method for different conditions, that is the gas flow and the time of deposition. The time of the aluminizing processes varied from 1.5 to 10 hours and the gas (HCl) flow varied from 0.4 to 1.4 l/min. Aluminum was deposited from the AlCl3 and zirconium from the ZrCl3 gas phases at 1040 oC. The obtained coatings were examined using an optical microscope (microstructure and coating thickness) a scanning electron microscope (chemical composition on the cross-section of the modified aluminide coating) and an XRD phase analyzer. Microstructures and phase compositions of coatings obtained at different process parameters do not differ significantly. In all cases, it is a triple zone structure. Chemical compositions of zones correspond to β-NiAl, γ’-Ni3Al and γ-Ni (Al) phases. The elongation of the time of zirconium-aluminizing process from 1.5 to 10 hours leads to the increase of the coating thickness from 30 to about 60 μm. The EDS analysis and concentration profiles of the cross-section of the coating showed the nickel outward diffusion from the substrate and the aluminum inward diffusion from the surface to the nickel substrate. In coatings deposited at a slow gas flow porosity was observed on the border between β-NiAl and γ’-Ni3Al layers. In coatings deposited at fast gas flow, zirconium does not form any inclusions but dissolves in the matrix. The Kirkendall porosity was not observed.

New refining technology of soda – calcium – silicon glass surfaces with inorganic compounds nanomolecules has been presented in the study. In order to determine modification of the glass surface SEM observation and EDX analysis have been carried out. The glass samples were subjected to the UV-VIS, photo-elasticity and ellipsometry examinations. From obtained results follows, that refining of the glass surface by nanopowder aluminum hydroxide compounds provides forming of very thin surface layers. This type of modification improves physical glass properties. As the example results of microhardness refined glass are presented in the article.Keywords: glass, surface, nanoparticles, refining

The paper presents basic methods of plasma spraying at very low pressure (<2 mbar). Described in the text are conditions which influence microstructure of Thermal Barrier Coatings obtained by these methods. A review and characteristics of the LPPS-TF system applied around the world has been provided.

The paper presents the influence of long-term heat treatment on aluminide coating. The MAR M-200 nickel superalloy was use as base material. The aluminide coating was deposited in low-activity chemical vapour deposition process using Ion Bond BPX Pro 325s device with following parameters: temperature 1040oC, time 12 hours, pressure 150 mbar. The samples (14 mm diameter) were annealed at 1020oC in vacuum for 12, 16 and 20 hours respectively. The XRD phase analysis and SEM microstructural observation with EDS analysis were conducted. The phase composition analysis showed that after deposition the NiAl phase is a main component of the coating. After the 20-hour-long annealing presence of Ni3Al phase in the coating was observed. Changes in structure of coatings and Al content during heat treatment were detected as well. The maximum duration of heat treatment performed for Ni superalloy with aluminide coating without significant changes in coating phase composition and microstructure is 16 hours.

The article presents the investigation of influence of long-term annealing of Zr modified aluminide coatings on its microstructure. The coatings were deposited by Chemical Vapour Deposition on MAR M200+Hf nickel superalloy. Annealing was carried out in a vacuum furnace at the temperature 1020oC within the period of 12, 16 and 20 hours respectively. The microstructral analysis was carried out using Hitachi S-3400 scanning electron microscope. Phase changes in the aluminide layer were observed, particularly the NiAl phase into Ni3Al. Changes in thickness of individual layers in the coating were observed. Conducted research showed that there is no influence of Zr on structure of the aluminide coating during annealing. The structure changes are similar to observed in simple aluminide coating. The maximum time of heat treatment without significant influence on structure of aluminide coating is 16 hours. After that time the main component of coating is NiAl phase.

A detailed study of thermal analysis of ZrCl4 was carried out to investigate the influence of the halide salt type activator on the growth behavior of coating formed in vapor phase aluminizing process and subsequently to identify the most suitable condition. The equilibrium partial pressures of vapor species generated at the decomposition temperature of ZrCl4 were calculated by using a procedure based on minimization of the whole Gibbs energy with Factsage 6.2 using Fact 53 and SGsold thermodynamic databases. The results were discussed and compared with literatures. With the aid of thermodynamic analytical tools, chloride salt activator was analysed and the decomposition temperature with related enthalpy change was evaluated.

Low pressure plasma spraying (LPPS) is one of the most advanced processes of an MCrAlY bond coat formation. It ensures the forming of metallic coatings free of oxides which can act as an bond coat for thermal barrier coatings used, among others, for protection of turbine blade surface. The paper presents results of tests into microstructure of coatings made from AMDRY 997 powder on the base of type Inconel 617 heat-resistant nickel alloy. The tests were carried out using light and scanning electron microscopy. Evaluated was the influence of spraying conditions on microstructure, porosity and thickness of the obtained coating. Test results show that the LPPS method allows to form coatings of low porosity and free of oxides which can be used as an bond coat in thermal barrier coatings.

The article presents the first attempt to CVD-aluminise alloys based on an intermetallic phase Ti48Al2Cr2Nb. Moreover, it includes initial results of producing VPA-deposited aluminide coating in industrial environment. Microstructure and phase analyses of the obtained coatings have been conducted. The chemical and phase composition analyses have revealed that the CVD-deposited coating was roughly 8 m thick, and composed of aluminium-rich TiAl phase, whereas the application of VPA method results in a coating which is approximately 18 m thick and consists of three layers made up of TiAl3, TiAl2 i TiAl phases. Both deposition processes were conducted with industrial equipment.

The article presents the experimental trial to connect aluminizing methods: VPA and CVD. Inconel 713 alloy was used as the base material. The purpose of the process was to obtain a layer modified with more Zr than the coatings deposited by CVD. The conducted tests revealed intercrystalline corrosion in the area of β-NiAl phase granules, which indicates that precise selection of processing conditions is the key factor for Zr-modified aluminizing. The resultant microstructural faults of the layer, however, didn’t impair the properties PS-PVD-deposited ceramic layer. The zirconium content in the outer zone equalled 2-3 at.%. in the second variety of the process. In future the described coating may form an alternative for Pt-modified aluminide coatings.

The paper presents the preliminary results of technological tests of aluminizing using a new BPX Pro 325 S CVD equipment. Nickel based cast superalloys: IN 738 and MAR M200+Hf were used as a substrate material. The aluminizing processes with different parameters - pressure, HCl flow and time - were conducted. Microstructure analysis showed coatings whose thickness didn't exceed 20 µm. The authors showed that the changes of parameters values in the analyzed range weakly influenced the coating thickness (about 1-2 µm). It was proven, that it was necessary to decrease the flow of hydrogen chloride and perform the thermodynamic analysis.

In the paper first results of TBCs deposition by LPPS-Thin Film method were presented. The LPPS-Thin Film is a new type of processes for deposition of thermal barrier coatings. In this method deposition of thin ceramic layer in very low pressure is possible as well as coatings with columnar structure (in plasma spraying-physical vapour deposition process). The MeCrAlY bond coats were deposited by APS method. The overaluminising by CVD method of conventional MeCrAlY was also conducted. The analysis of microstructure of both type bond coats as well as outer ceramic layer were presented using light and scanning electron microscopy methods. Results of EDS microanalysis showed the increasing of aluminum content in outer zone of overaluminized MeCrAlY coating. In ceramic layer the columnar structure were observed which was connected with powder evaporation during plasma spraying. The new type of MeCrAlY-NiAl bondcoat could increase the oxidation of TBCs deposited by LPPS Thin Film method.

The Zr modified aluminide coatings is an alternative concept for replacing Pt-modified aluminide bondcoat for thermal barrier coatings. In the paper the influence of process parameters on the chemical composition and the thickness of aluminide coatings will be presented. The zirconia-doped aluminide coating was deposited on turbine blades made from ZS6K nickel superalloy during the low-activity CVD process. In recent work the influence of turbine blade geometry on thickness of coating was observed. The thickest coating was observed on the trailing and leading edge on the blade cross-section. In the conducted research, the light and scanning electron microscopy were used as well as the EDS chemical composition microanalysis.