Cast Turbine Blades Research Articles

A novel framework for low-contrast and random multi-scale blade casting defect detection by an adaptive global dynamic detection transformer

The radiographic inspection plays a crucial role in ensuring the casting quality for improving the service life under harsh environments. However, due to the low-contrast between the defects and the image background, the random spatial position distribution, random shapes and aspect ratios of the defects, the development of an accurate defect automatic detection system is still challenging. To address these issues, this paper proposes a novel framework for low-contrast and random multi-scale casting defect detection, which is referred to as adaptive global dynamic detection transformer (AGD-DETR). A novel defect-aware data augmentation method is first proposed to adaptively highlight the feature of the low-contrast defect boundary. A multi-attentional pyramid feature refinement (MPFR) module is then established to refine and fuse the multi-scale defect features of random sizes. Afterwards, a novel global dynamic receptive fusion-transformer (GDRF-Transformer) detection scheme is designed to perform the global perception and feature dynamic extraction of complex internal casting defects. It includes 4D-anchor query and cross-layer box update strategy, query rectification by prior information of defect aspect ratio, and global adaptive-feed forward network (GA-FFN). A dataset comprising turbine blade casting defect radiographic (TBCDR) images, is used to demonstrate the high efficiency of the proposed AGD-DETR. The obtained results show that the proposed method can accurately capture the spatial position distributions and complex defect shapes. Furthermore, it outperforms existing state-of-the-art defect detection methods.

Innovative ceramic paste for stereolithography additive manufacturing alumina core applied in turbine blade casting

AbstractCeramic stereolithography 3D printing technology has demonstrated great potential in alumina core manufacturing for advanced turbine blade casting. However, there have been very few photosensitive material formulas specifically designed for alumina core fabrications. Herein, we present the design of a 3D printable ceramic paste based on bimodal particle size distributions for additive manufacturing of high‐quality alumina cores. The coarse particles in the paste remain in their original shape while the fine particles transform into platelet‐like particles during sintering. The effects of coarse particles, platelet‐like particles, and grain growth on maintaining porosity and limiting shrinkage rates are studied. Furthermore, the vacuum sintering process is found to be beneficial for core material properties. The physical properties tests verify that the newly designed alumina paste in this work can meet the application requirement, which is superior to the previous research.

Silica-based ceramic cores for high-pressure turbine airfoil blades in aircraft engines

Ceramic cores for high-pressure turbine airfoil blades in aircraft engines are characterised by very complicated shapes and the presence of small diameter holes and thin long grooves. In this paper, eight starting powder mixtures having different contents of fused silica, zirconium silicate, alumina and borosilicate glass were used for preparation of core material. The composition, which satisfies every demand for core application in the investment casting of high-pressure turbine blades, contains 69.0wt.% fused silica, 13.0 wt.% zirconium silicate, 12.0wt.% alumina and 6.0wt.% borosilicate glass. This material was characterised by a mechanical strength of 33.1MPa, a coefficient of thermal expansion of 2.56 ? 10?6 1/K, surface roughness of 1.8 ?m, shrinkage of less than 0.8% and an average pore size diameter of 2.7 ?m. The thin-walled ceramic cores were formed by the high-pressure injection moulding method, which required the selection of a thermoplasticiser, feedstock formulation and determination of the optimal processing conditions protecting the injected cores from defects and deformation. The post-shaping process of the cores included both water and thermal debinding, sintering, precision machining and dimension measurements.

Cooling performance of film-cooling holes fed by channels of various shapes

Internal and external cooling is pertinent to maintaining operable surface temperatures of hot-section gas turbine components. Film cooling on the external surfaces is supplied from cooling passages placed inside of the blades and can affect the external film-cooling performance. Assessing internal cooling designs that were once difficult to investigate because of the complexity and costs of manufacturing cast turbine blades is now possible to more quickly and less costly through additive manufacturing (AM).This paper provides results and analysis of an experimental and computational study of the cooling performance of meter-diffuser shaped film-cooling holes fed by a range of individual channel shapes with different cross-sectional shapes: circle, hexagon, pentagon, ellipse, diamond, square, rectangle, trapezoid, triangle – vertex up, and triangle – vertex down. These geometries were made possible through the use of AM. The perimeter, and consequently the surface area of the supply channels to the cooling holes, was maintained constant between the different channel shapes. The predictive computational results showed that the shape of the channel affects the secondary flows through the hole that in turn affects the overall film cooling as determined experimentally. The triangle – vertex up created flow structures in the diffuser-shaped cooling hole that caused the coolant jet to create a film on the surface with wide lateral spread; whereas the triangle – vertex down created flow through the cooling hole that caused the jet to fully detach at the same blowing ratio. Consequently, the triangle – vertex up had a 14% improvement in overall effectiveness over the triangle – vertex down and a 33% improvement over the circle which had the lowest overall effectiveness of all the tested shapes.

Reinforcement of silica-based ceramic cores based on amorphous and polycrystalline mullite fibers

In the investment casting of turbine blades, ceramic cores are key components to form complex hollow structures. Superior mechanical property and leaching rate are demanded for ceramic cores. Herein, ceramic cores were fabricated using fused silica powders as the matrix, and amorphous and polycrystalline mullite fibers as the reinforcement phases, respectively. The microstructure and property evolution of ceramic cores rely on the crystallization degree of mullite fibers are explored. Both of the mullite fibers lead to improved crystallization of cristobalite, reduced sintering shrinkage, increased apparent porosity, and benefited bending strength, creep resistance, and leaching rate of the cores. Compared to the polycrystalline mullite fibers, the amorphous fibers are metastable with large quantities of structural defects, promoting the diffusion mass transfer and forming strong interface between fibers and matrix. Therefore, the amorphous fibers have larger promotion on the bending strength and resistance to creep deformation of ceramic cores. Moreover, the structural defects of amorphous fibers ensures the high chemical activity in alkaline solutions and exhibits excellent leaching rate. The ceramic core with 4.5 wt% of amorphous mullite fibers exhibits excellent comprehensive performance with bending strengths of 28.9 MPa and 23.8 MPa at room temperature and 1550 °C, creep deformation of 0.3 mm, and leaching rate of 1.4 g/min, well meeting the casting requirements of hollow blades.

Influence of debinding parameter and nano-ZrO2 particles on the silica-based ceramic cores fabricated by stereolithography-based additive manufacturing

The silica-based ceramic core is an essential part of the investment casting of hollow turbine blades due to their excellent thermal stability and easy demoulding. In this study, the green bodies of silica-based ceramic cores with nano-ZrO2 were fabricated by stereolithography (SLA). Firstly, the effects of the burying process and debinding heating rates on the performance and microstructure of silica-based cores were investigated. The results revealed that the burying powders provide support and a stable thermal field for the SLA ceramic cores during debinding and sintering. Ceramic cores with smaller shrinkage and higher apparent porosity were produced during the burying process at a heating rate of 0.5 °C/min. In addition, the influence of nano-ZrO2 content on the mechanical properties of silica-based ceramics was investigated. Nano-ZrO2 particles can improve bulk density and mechanical properties by promoting sintering. Additionally, it can reduce the cracks on the surface of ceramic samples. The optimal content of nano-ZrO2 should be between 1.5 and 2 wt%, producing silica-based cores with low shrinkage rate (2.91–3.19%), high apparent porosity (27.11–27.97%) and high flexural strength at room temperature (24.51–24.65 MPa) and high temperature (27.81–29.69 MPa). This work provides promising ways to fabricate high-quality ceramic cores for turbine blade application.

Investigation of microstructure evolution and properties in silica‐based ceramic cores with alumina as a mineralizer

AbstractIn this work, silica‐based ceramic cores with alumina as a mineralizer were prepared via an injection molding method, and the effects of alumina on the microstructural evolution and properties at 1450°C (simulating the process of equiaxed castings) and 1550°C (simulating the process of columnar/single crystal castings) were investigated. It was found that alumina promoted the cristobalite crystallization of fused silica refractory during sintering but inhibited the devitrification rate in the subsequent heating. The flexural strength of silica‐based ceramic cores at an ambient temperature and 1450°C improved with an increasing alumina content, whereas the opposite trend appeared at 1550°C. The creep resistances of silica‐based cores were improved significantly and then slightly deteriorated with an increasing alumina content from 5% to 20%, depending on the competition effects of alumina hindering the viscous flow of liquid silica (favorable), but suppressing the devitrification rate (unfavorable). The results of this work show that silica‐based cores need to follow different compositional design principles for equiaxed and columnar/single‐crystal turbine blade castings.

3D printing of silica-based ceramic cores reinforced by alumina with controlled anisotropy

Ceramic core (CC) is a key component in the casting of aero-engine turbine blades, and CC through 3D printing is crucial to the growing aviation technology. However, these silica CCs are highly limited by their high temperature softening and inevitable anisotropy. In this work, silica-based CCs reinforced by alumina powders are manufactured by 3D printing via digital light processing (DLP) stereolithography, and the anisotropy in microstructure and property was investigated. In the CC without alumina powders, multilayer structures with significant interlayer gaps are exhibited in horizontal printing direction suggesting significant anisotropy in microstructure, which is related to the particle deposition in printing. As the alumina content is 6 wt%, microstructures become uniform, due to the enhanced particle rearrangement between different layers. To assess the mechanical anisotropy, the ratio of vertical strength to horizontal strength (σV/σH) is raised, and the σV/σH ratios rise from 0.45 to 0.86 at room temperature and 0.52–0.89 at 1540 °C with increasing alumina content from 0 to 6 wt%. As the alumina content is 6 wt%, the CC exhibits high temperature flexure strengths as high as 17.9 MPa and 19.5 MPa in different directions, well satisfying the demands for turbine blades casting. This article inspires a profound understanding on the anisotropy control in 3D printing of CC with excellent high-temperature mechanical properties.

Development of mullite-alumina ceramic shells for precision investment casting of single-crystal high-pressure turbine blades

Alumina-mullite ceramic shell moulds were developed to cast single-crystal hollow high-pressure turbine blades (SX-HPTB). Mullite and fine alumina powders were used as fillers. Two colloidal silica binders were used to bind the filler particles. One colloidal silica binder (binder A) had no polymer and the second colloidal silica binder (binder B) had 8 wt % polymer. Eight slurry compositions with fine alumina substitution (0, 10, 30 and 50 wt %) were prepared. Silica cores were used to achieve hollow castings. The effect of alumina substitution and binders on the slurry characteristics, flexural strength of green and fired samples, air permeability and self-load sag resistance was studied. It was observed that with an increase in alumina percentage, the test specimens showed increased viscosity, pick-up weight, density, green strength and fired residual strength. In addition, the slurries prepared from binder B possessed larger values of viscosity and pick-up weight compared to the slurries prepared from binder A. The residual strength of fired test specimens containing binder A was higher than those containing binder B. The test specimens with 30 wt % fine alumina substitution showed the highest self-load sag resistance w.r.t. each test temperature. Also, the air permeability of the fired samples was higher than the green (de-waxed) samples. The casting of hollow HPTB components was performed at two temperatures (1525 °C and 1550 °C) using nickel-based superalloy CMSX4. The HPTB components, cast at 1550 oC from ceramic shell mould having binder B and 30 wt % fine alumina substitution, resulted in an acceptable aerofoil profile and surface roughness.

The effect of conditions of directional crystallization on the structure of cast blades made of nickel superalloys

The characteristics of gas turbine engines depend on the structural state of the material of the turbine blades and are largely determined by the technology of their manufacture. Identification of the specific defects of casting is an important goal aimed at improving the quality of blade castings since the castings of turbine blades with a monocrystalline structure made of high-alloyed nickel superalloys (NS) are subject to increased requirements for macro- and microstructure. We present the results of studying the effect of directional crystallization parameters on the morphology of the dendritic structure of NS and their tendency to form casting defects of the single-crystal structure. The structure of alloys in single-crystal blade castings and the effect of technological parameters on the dispersion of the structural components of NS were analyzed upon casting of turbine blades with <001> axial orientation on installations with liquid-metal cooling. It is shown that the parameters of the dendritic cells of castings vary in height from 220 to 330 μg and volume fraction of micropores changes from 0.02 to 0.2%. Electron probe microanalysis revealed that the phase and local elemental compositions of the alloy in the areas of the blade tip and isolated grains are identical. The appearance of isolated grains that violate the monocrystalline structure of castings is observed when the rate of NS cooling decreases. To increase the temperature gradient and reduce the probability of formation of extraneous crystals in castings ahead of the crystallization front, optimized temperature-speed modes of casting and directional crystallization are proposed. The obtained results can be used in the development of temperature-velocity parameters of the process of directional crystallization of blades of promising turbines made of new superalloys.

Interior-collapsing mechanism by hydrothermal process of the MgAl2O4/MgO porous ceramic

Ceramic core is a critical component in the super-alloy turbine blade casting. In our previous work, a novel multi-phase MgAl2O4/MgO porous ceramic was prepared for this purpose. The most important property was that it crumbled completely after hydrothermal treatment in just pure water, due to the hydration of MgO. In this work, the hydration process of the MgO embedded in the inert matrix was investigated in detail. The collapse behaved as an interior destruction without any bulk expansion of the sample. The hydration percentage was the only factor related to the water-collapsibility. The morphology of hydration product indicated that the reaction advanced in particular direction. Based on the finite element analysis for the expansion effect on the porous structure, the interior-collapsing mechanism was proposed. During the hydration process, the MgO grains exerted pressure to the surrounding matrix and induced the collapse in the adjacent structure. This process took place throughout the matrix. Finally, the sample crumbled completely to the powders. No bulk dilatation was detected before the powdering, indicating that the collapse process would not exert pressure outward. Thus the alloy blade would not be damaged during the removal of the ceramic core. It was also predicted that the decrease in the MgO grain size was beneficial to the water-collapsibility.

Anisotropy management on microstructure and mechanical property in 3D printing of silica-based ceramic cores

Ceramic core is an essential component in the precise casting of hollow turbine blades, and the investigation on 3D printing of silica-based ceramic cores is crucial to the development of aviation industry; however, they are suffered from difficulty in high-temperature strength and structural anisotropy. In present work, silica-based ceramic cores were prepared via DLP stereolithography 3D printing, and the anisotropy management on microstructures and properties were explored based on the particle size of fused silica powders. In 3D printed ceramic cores with coarse powders, significant anisotropy was displayed exhibiting multilayer structure with large gaps in horizontal printing and uniform porous microstructure in the vertical direction, which was further explained by the particle deposition in printing. With finer silica powders, the uniformity in the microstructures was highly improved, attributed to the enhanced particle dispersion in ceramic slurries and promoted interlayer particle rearrangement during sintering. To evaluate the anisotropy in mechanical property, the ratio of vertical strength to horizontal strength (σV/σH) was proposed, which rose from 0.48 to 0.86 as the particle size decreased from 35 µm to 5 µm, suggesting enhanced mechanical uniformity. While the average particle size of silica powders was 5 µm, the flexure strengths of ceramic cores in different directions were up to 18.5 MPa and 16.3 MPa at 1540 °C with σV/σH ratio of 0.88, which well satisfied the demands for the casting of turbine blades. This work inspires new guidance on the anisotropy management in ceramic cores prepared by 3D printing, and provides new technology for fabrication of silica-based ceramic cores with superior high temperature mechanical properties.

A comprehensive understanding of grain selection in spiral grain selector during directional solidification

• The grain selection in spiral selector is a coupling process where high order dendrites branch in the front side and primary dendrites disappear in the back side. And it is influenced by a combination effect of “space expansion mechanism”, “geometrical restriction mechanism” and “competitive grain growth”. • The smaller of the take off angle (θ) is, the larger space and the stronger driving force high order dendrites will get, and the higher efficiency the selector will be • Grain with preferred secondary dendrites instead of preferred primary dendrites could outcompete during grain selection, and this is the reason why spiral grain selector cannot optimize the orientation of the primary dendrites. It is of great importance to further investigate grain selection mechanism for the production of single crystal (SX) turbine blade because a single crystal with optimized crystal orientation will enhance service performance of the blade severely. In this paper, single crystals with different deviation angles, i.e. 6°, 12° and 29°, were obtained using directional solidification under the same casting conditions. It has been found that the grain selection in spiral selector is a coupling process where high order dendrites branch in the front side and primary dendrites disappear in the back side based on the metallographic analysis and electron back scatter diffraction (EBSD). Considering the development of liquid/solid interface by numerical simulation, a combination effect with space expansion, geometrical restriction and grain competition was proposed for spiral grain selection. The space expansion mechanism dominates the process as it provides growth space and driving force for high order dendrites advancing. Thereby, the smaller the take-off angle ( θ ) is, the larger space and the stronger driving force high order dendrites will get, and the higher efficient the selector will be. The competitive growth between the secondary dendrites plays more contribution than that of primary dendrites, i.e. grain with preferred secondary dendrites instead of preferred primary dendrites could outcompete during grain selection, and this is the reason why spiral grain selector cannot optimize the orientation of the primary dendrites. These findings provide experimental evidence for spatial control of SX growth, and benefit the sophistic casting fields such as turbine blade casting for improved yield.

Additive manufacturing of low-shrinkage alumina cores for single-crystal nickel-based superalloy turbine blade casting

We prepare bimodal particle size photo-curable ceramic pastes with high solid loadings (up to 65 vol %) and fabricate porous alumina ceramic cores with complex shapes via ceramic stereolithography (Cer-SLA) 3D printing technique. The sintering temperature is carefully selected, ranging from 1500 °C to 1650 °C, and a high holding time (>4 h) is applied to guarantee that the materials can withstand the subsequent high temperature (>1500 °C) casting process for single-crystal nickel-based superalloy hollow turbine blades. Herein, the originally spherical fine particles are found to become platelet-like after sintering, and the forming mechanism is discussed in detail. In addition, we explore the influence of platelet-like particles, coarse particles and sintering process on the microstructural evolution of alumina particles, and reveal the relationship between microstructure and properties of ceramic cores. These results illustrate that the proposed materials for SLA 3D printing exhibit a great potential in the fabrication of complex-shaped alumina ceramic cores for high-precision investment casting, e.g., manufacturing single-crystal nickel-based superalloy hollow turbine blades for an advanced aircraft engine.

Some aspects of improving the quality of GTE cast turbine blades of nickel superalloys

The results of the development of casting technology for single-crystal high-pressure turbine blades from nickel superalloys with a crystallographic orientation (CGO) [001] were obtained on an automated casting unit for directional crystallization UVNK-9A, at machine-building enterprise. The construction of the casting blades blocks, technologies for the manufacture of molds, rods and casting of GTE working blades of heatresistant nickel alloys with a single-crystal structure and set-up CGO have been developed under real production conditions on UVNK-9A units substituting through-type furnaces. It is shown that preproduction series of single-crystal castings of working blades with shroud shelf were obtained, with a yield of suitable structure ≥ 75%. The structural-phase characteristics of the alloy of single-crystal blades castings were investigated by scanning electron microscopy in as cast state and after subsequent heat treatment. A comparative quantitative analysis of the microstructure and strength characteristics of supernickel alloy castings with CGO [001], obtained on a high-gradient directional crystallization unit and in a through-type furnace.

ОСОБЕННОСТИ РАЗРАБОТКИ ТЕХНОЛОГИЙ ИЗГОТОВЛЕНИЯ И УДАЛЕНИЯ КЕРАМИЧЕСКИХ СТЕРЖНЕЙ НА ОСНОВЕ ПЛАВЛЕНОГО КВАРЦА ДЛЯ ЛИТЬЯ ТУРБИННЫХ ЛОПАТОК ИЗ ЖАРОПРОЧНЫХ НИКЕЛЕВЫХ СПЛАВОВ

Technological parameters of removal of ceramic cores based on fused quartz from the inner cavity of turbine blade castings are selected and investigated. The results of studies of technological parameters of removal of ceramic cores based on fused quartz are presented, according to the results of which optimal technological parameters are selected and a technology for removing ceramic rods from fused quartz from the inner cavity of turbine blade castings is developed.

3D printing ceramic cores for investment casting of turbine blades, using LCD screen printers: The mixture design and characterisation

The primary objective of this study is to demonstrate the possibility of developing silica, alumina, and zircon-based photocurable ceramic suspensions that can be used for visible light photopolymerization (> 450 nm) and to optimise the binder formulations for the purpose of LCD-based ceramic 3D printing applications. Reference ceramic components for this work are ceramic cores employed in the investment casting of high-pressure turbine blades and vanes. Arguably, one of the most critical steps in photoinduced ceramic 3D printing is developing suitable ceramic suspensions, having high ceramic loading, low viscosity, and short curing times. Ceramic suspensions with four different novel binder formulations and commercial ceramic powders used in core manufacturing (SiO2, Al2O3 and ZrSiO4) were investigated to achieve the best trade-off between: (1) their curing performance (cure depth and curing speed), (2) rheological properties of the binder mixtures at the solid loadings of 60 vol.% for SiO2, 55 vol.% for ZrSiO4, and 45 vol.% for Al2O3; and (3) the green body mechanical properties of the mixtures after printing. The effect of ceramic particles on the selected binders was examined individually, and the correlation between cure depth (Cd), volumetric loading, and curing speed are evaluated. The results show all binders designed in this study provide an adequate cure depth, even at high ceramic loadings. When the curing behaviour of all unloaded binder mixtures from the previous study [1] compared with the 10 vol.% SiO2 loaded mixtures, the cure depth of all formulated binder mixtures increased 50–55 % and the curing thickness of 60 vol.% SiO2 loaded suspensions were still slightly higher than their unloaded counterparts. The rheology outcomes indicate that lower viscosity binders always result in lower viscosity of the ceramic loaded inks, even without taking the effect of dispersants into account. Besides, the addition of N-Vinyl-2-Pyrrolidone (NVP) monofunctional monomer to the binder mixtures significantly reduces the viscosity and changes the normally linear relationship of the mix viscosity and its silica loading content. Among the binder formulations loaded with 60 vol.% of SiO2, the formulation providing the lowest viscosity and highest mechanical property consists of 5 wt.% of NVP, 45 wt.% of HDDA and 50 wt.% of Photocentric 34 resin. Although this binder mixture showed the highest green flexural strength when loaded by 55 vol.% ZrSiO4, all other mixtures loaded with zircon flour also demonstrated a near-fluid behaviour, below 200 s−1. In Al2O3 loaded mixtures, the HDDA di-functional binder formulations present lowest viscosity and the di- and multifunctional monomer blends (HDDA-Photocentric27) showed the highest mechanical properties when used in a 50/50 ratio. This work summarises the best binder choices for silica, alumina and zircon based ceramic suspensions used in core printing for investment casting applications through LCD screen printing.

A novel MgAl2O4/MgO ceramic core with water-collapsibility

Ceramic cores are the critical components in the hollow turbine blade casting. Due to the rigorous requirements for both high temperature creep resistance and the removal performance, only a few material systems can be applied to this area. However, each of them also has disadvantages on either of the two conflicting requirements. In order to conquer this difficulty, a novel multi-phase MgAl2O4/MgO ceramic was fabricated by reaction sintering in this work. The obtained materials had the porous structure of MgAl2O4 embedded by MgO minor phase, and its creep resistance at 1550 °C was even better than alumina ceramics. More importantly, the removal of the multi-phase ceramic can be fulfilled via hydrothermal treatment in pure water. A new mechanism was revealed that the collapse was caused by the volume expansion during hydration of the MgO grain rather than the corrosion or dissolution. The MgO grain embedded in the porous structure served as a structure-shatter phase. This material has enormous potential in the application of ceramic core.

Effect of CaO and SiO2 on the properties of Y2O3-based ceramic core materials

ABSTRACT Nb-Si alloy is an important candidate material to produce hollow turbine blades in the aerospace industry. However, the ultra-high melting temperature of Nb-Si alloy (≥1750°C) makes the traditional ceramic core made of Al2O3 (poor leachibility) or SiO2 (melting temperature) invalid in the production of Nb-Si hollow turbine blades. In this study, Y2O3 were used as the ceramic core matrix due to its high melting points, high strength, and low interfacial reactivity. CaO and SiO2 were added in Y2O3 matrix to improve the leachability and high temperature flexural strength (1500°C) of ceramic cores. The other properties such as porosity, shrinkage and bulk density were investigated as well. The results showed that the introduction of CaO in Y2O3-based ceramic cores improved the leachability. The addition of SiO2 in the Y2O3-CaO matrix could greatly improve the high temperature flexural strength, and keep a good leachability at the same time. The best comprehensive properties of Y2O3-based ceramic cores were obtained when it contained 12 wt% CaO and 4 wt% SiO2. The new developed Y2O3-based ceramic cores with the addition of CaO and SiO2 has the potential to meet the extreme requirements in the casting of Nb-Si alloy hollow turbine blades.

РАЗРАБОТКА НОВОГО ЖАРОПРОЧНОГО НИКЕЛЕВОГО СПЛАВА ВЖМ200 И ТЕХНОЛОГИИ ЕГО ПРОИЗВОДСТВА ДЛЯ ЛИТЬЯ МЕТОДОМ НАПРАВЛЕННОЙ КРИСТАЛЛИЗАЦИИ РАБОЧИХ ЛОПАТОК ПЕРСПЕКТИВНЫХ ДВИГАТЕЛЕЙ

FSUE «VIAM» has developed a new nickel-based superalloy VZhM200 and its manufacturing technology for casting of turbine blades with directional (pillar-type) structure for advanced turbine engines. The advantages of the VZhM200 alloy over the DS200 Hf alloy are presented in the article. The quality of VZhM200 alloy produced by FSUE «VIAM» meets the DS200 Hf, MAR M200+Hf alloys produced by Cannon-Muskegon Corporation and HOWMET Ltd in chemical composition, content of harmful and non-metal impurities, gases and mechanical properties.