Application Of Additive Technologies Research Articles

Application of Additive Technology in Precision Casting

In this paper the surface of the prepared test specimens had been examined with light microscopy and surface roughness measurements. In order to improve the surface smoothness of PLA specimens, application of ethyl acetate was required. After this surface treatment, microscopic images were taken again. The melting and decomposition temperatures of the materials had been determined using derivatography. The chosen method was precision casting with gypsum molding. Also, the plaster molds had been burnt out according to the predefined melting and firing diagram. The measurement series shows that the samples produced by 3D printing can also be used in the field of precision casting. They provide greater freedom of design, more sophisticated pieces, and prototypes can be finished in a shorter amount of time.

Application of additive technologies for manufacturing turbine stator parts in aircraft engines

Continuous development of additive technologies and fast prototyping methods makes it possible to use them in manufacturing of complex shape models to a high precision. The traditional technological manufacture process of critical hot gas path parts by investment casting is expensive and time consuming in view of its technological complexity. It is related to the wax casting process which provides complex profiles with high geometrical accuracy. The acceleration of the investment casting process should increase the productivity of the manufacturing process of such hot gas path parts as the turbine stator, however, it is not allowed to decrease the geometric accuracy of the finished product. The aim of this work is to compare technological processes for manufacturing turbine stator parts at various temperatures using the fast prototyping method (wax casting in silicone molds). The dimensional analysis of the stator castings showed that casting in silicone molds provides the required geometric accuracy. Thus, silicone molds can be viewed as a good cost-effective solution for small-scale or pilot production of high-precision complex parts in gas turbine engines. This article describes the procedure for the integrated application of additive technologies and thermographic analysis to accelerate the investment casting process by determining the optimal temperature conditions and cooling period. Ultimately, it reduces the duration of the production cycle and the cost of the finished product while retaining the quality characteristics.

Obtaining and Research of Additive Products from Electroerosive Cobalt-Chrome Powders

Based on the particularity of the methods of obtaining spherical shape powders in order to obtain spherical granules of a regulated grain size, the technology of electroerosive dispersion, which is distinguished by relatively low energy costs and ecological cleanliness of the process, is described. The widespread use of the method of EED for the processing of metal waste into powders for the purpose of their reuse and application in additive technologies is constrained by the lack of complete information in the scientific and technical literature about the influence of the original composition, modes and media on the properties of powders and technologies of practical application. Therefore, the development of technologies for the reuse of EED powders and the evaluation of the effectiveness of their use requires the conduct of comprehensive theoretical and experimental studies. The purpose of this work was to obtain and study additive products from electroerosive cobalt-chromium powders of a specific particle size distribution and to study their microstructure. The granulometry of the obtained powders was determined on a laser analyzer of particle sizes “Analysette 22 NanoTec”. The microstructure of additive samples from cobalt-chromium powders was investigated by optical microscopy on an inverted optical microscope OLYMPUS GX51. On the basis of completed studies, aimed at obtaining and studying additive products from electroerosive cobalt-chrome powders of a specific particle size distribution, and studying their microstructure, it was found that additive samples, obtained from a cobalt-chrome powder with an average particle size of 35.68 μm, have practically no pores.

The wear resistance additive products derived from EED cobalt powder

The main claim for powders for additive 3D technologies is a spherical shape of particles. Such particles are the most compact, packed in a certain volume and provide "fluidity" of the powder composition in the material supply systems with the least resistance. The wide use of the method of metal waste recycling into powders for their reuse and application in additive technologies is constrained by the lack of scientific and technical literature complete information on the impact of the original composition, modes and environment on the powder properties and practical application technologies. Therefore, comprehensive theoretical and practical researches are required to develop technologies for the reuse of electro-erosion powders and to estimate the effectiveness of their use. The aim of the work was to study the wear resistance of additive product samples, obtained from cobalt-chromium electro-erosion powder. The wear resistance of the samples was studied on a high-temperature tribometer manufactured by CCM tools. The friction coefficient (initial, maximum and average) is determined on the basis of the wear resistance assessment. The wear coefficient value of the statistical partner and the wear coefficient of the electric spark coating were also identified. The visual image of the wear trace and the wear groove profile of the electro-spark coating are shown.

ПРИМЕНЕНИЕ АДДИТИВНЫХ ТЕХНОЛОГИЙ В СТРОИТЕЛЬСТВЕ И ПРИ ИЗГОТОВЛЕНИИ КЕРАМИЧЕСКИХ ИЗДЕЛИЙ

Additive technologies that allow creating volume objects of different complexity are becoming popular in different industries. There is an increase in the scale of introduction of 3D printing technologies in the construction industry, including in the production of ceramic products. With the help of modern additive technologies, different models, products and designs are created. They can be complex and can be made from different materials. Experts are wondering what the future holds for additive technologies in construction, as well as in ceramic production, as these technologies can save resources, reduce the time of the technological process and form complex shapes.
 The article presents an analytical review of the global application of additive technologies in construction, as well as in the manufacture of ceramic products. The advantages and disadvantages, the possibilities of 3D printing are considered. The creation of ceramic three-dimensional products is still a rare area of additive technologies that requires research. The production of ceramic products, superior to other materials in terms of high temperature strength, hardness, chemical and thermal resistance, has a high potential for the use of additive technologies. The types of construction 3D printers and raw materials for them are analyzed. The results of a study of the properties of clay raw materials of the Sannikovsky, Namtsyrsky and Kangalassky deposits of the Republic of Sakha (Yakutia) are presented.

The Phase Composition of Products from Electro-Erosive Cobalto-Chrome Powders, Obtained by Additive Technologies

The main requirement for powders for additive 3d technologies is the spherical shape of the particles. Such particles are most compactly packed into a certain volume and ensure the "fluidity" of the powder composition in the supply systems of the material with minimal resistance. The wide use of the EED method for processing metal waste into powders for the purpose of their reuse and application in additive technologies is hampered by the lack in the scientific and technical literature of full-fledged information on the effect of the initial composition, regimes and media on the properties of powders and technologies of practical application. Therefore, in order to develop technologies for the reuse of electroerosive powders and to evaluate the effectiveness of their use, complex theoretical and experimental studies are required. The aim of the work was to conduct a phase analysis of additive products from electroerosive cobalt-chrome powders. The phase composition of the samples was studied by X-ray diffraction on a Rigaku Ultima IV diffractometer in Cu-Kα radiation (wavelength λ = 0.154178 nm) using Soller slits. Based on the results of the X-ray diffraction analysis of additive articles from electroerosion cobalt-chrome powders, it has been experimentally established that the main phases in the sintered samples are Co, Cr and Co3C.

Synthesis of Ultra-Dispersed Spherical Composite Materials

This paper describes a method of laser synthesis of titanium microspheres, titanium carbide and silicon oxide. The formation of microspheres is carried out under the action of femtosecond laser radiation on the surface of the sample. The analysis was carried out on a scanning electron microscope. The obtained titanium and titanium carbide microspheres have an average size of the main fraction of 1-3 μm and can be used in applications of additive technologies and powder metallurgy as the main raw material or as an alloying additive. The main fraction of silicon oxide granules lies in the range of 50-300 nm. To improve the efficiency of the particle output, a combined method of laser action and electric current is proposed.

Economic efficiency of the application of additive technologies based on laser direct metal tooling in the production of aircraft parts

The paper discusses the issues of the feasibility study on the integration of additive manufacturing technologies into classical technological chains. Using the aviation part as an example, we consider a model for the formation of technological costs for the classic and proposed versions of its manufacturing technology. A comparative parametric analysis of the cost of production of aircraft parts of this type was performed according to two options.

СПЕЦИАЛИЗАЦИЯ КАК СИСТЕМНЫЙ ИНСТРУМЕНТ РАЗВИТИЯ ШВЕЙНОЙ ПРОМЫШЛЕННОСТИ В УСЛОВИЯХ ЦИФРОВИЗАЦИИ

The development of digital technologies offers a wide range of opportunities to increase production efficiency, which relies on known tools and methods that transform in modern conditions. Many researchers note that the specialization most characteristic of complex knowledge-intensive industries has high prospects and is evident in all sectors of the national economy. Its combination with cooperation and outsourcing brings momentum to the development of both individual enterprises and the industry as a whole. It has been found that in light industry, which had a developed system of specializations, the return to this practice is difficult due to significant changes in the industries related to the liquidation of large mass production enterprises and the lag in the creation of digital twins, which are the basis at the stage of production preparation. Lost in the process of transition to a market economy, large production with a complete cycle is now successfully replaced by specialized small and medium-sized production, using high-performance equipment combined with modern digital technologies. It is obvious that the garment industry has entered a new cycle of development characterized by a high degree of specialization against the background of the application of digital technologies at all stages of the product life cycle. The significant lag in the application of digital technologies at the stage of production of light industry products is overcome, especially in the transition to additive technologies. It is noted that the digital shadow complements the information digital twin, which is especially relevant from the point of view of production. The introduction of digital technologies in specialized industries allows to achieve higher productivity and payback of invested capital than in standard production, where such investment is "blurred" due to the lag of related processes of the enterprise. It has been revealed that the modern stage of development of light industry is characterized by the application of fundamentally new technologies based on the creation of a digital twin and digital shadow, which create prerequisites for industrial application of additive technologies in industry. Key words: specialization, cooperation, digitalization, development of light industry

Prospects of application of additive technologies to develop parts and components of gas turbine engines and ramjets

The possibility of reducing the weight, simplifying the design, reducing the time and cost of development, production and operation are important advantages in the implementation of additive technologies (AT). The use of AT can significantly improve fuel efficiency, environmental and other characteristics of aircraft engines. The possibility of using AT in the production of various parts and components of engines is being currently investigated at CIAM. Examples of these developments, advantages of the use of AT and problems arising in the implementation of these technologies are presented in this article. Models of turbine blades with a highly efficient cooling system, in particular, with penetration cooling were designed and manufactured using optimization methods and taking into account the capabilities of AT. The possibilities of using AT for the manufacture of elements of molds for precision casting of gas turbine engine (GTE) blades of heat-resistant alloys and ceramic rods are shown. Elements of a two-zone front module of the low-emission combustion chamber of an advanced GTE are designed and manufactured using the AT method. Research of prospective branched tree channels of heat exchangers with mutually porous bodies that can be made only by AT methods and the use of which will make it possible to increase the efficiency of heat exchange in the case of lower weight, than that of the structures made by traditional technologies, is being carried out. The AT was used to manufacture complex elements of a ramjet engine. Fire tests of printed sections of the combustion chamber were carried out successfully. Cellular structures to be used in gas turbine engine parts with the aim of reducing their weight were developed. A hollow blade model with cellular-type core was made using AT. Tests of the designed cellular prototypes were carried out. The possibilities of reducing the mass of structural elements using cellular structures obtained by AT methods are shown. Research of hollow disks of turbines and other engine components produced with the aid of AT are carried out. Despite the fact that experimental studies of structural elements obtained by additive technologies have not been completed yet, these works show the prospects for the use of AT in the development of a wide range of engine parts and components.

Опыт применения аддитивных технологий для реконструктивных операций в челюстно-лицевой хирургии

Introduction. Modern technologies make it possible not only to plan reconstructive surgery virtually, but also to manufacture templates for resection and osteotomy, customized titanium plates based on the results of planning.
 Objective. To analyze the results of application of additive technologies for planning and performing reconstructive operations in the Maxillofacial Surgery and Stomatology Center at Burdenko Main Military Clinical Hospital 
 Patients and Methods. 144 operations to eliminate different locations bone defects were performed in the Maxillofacial Surgery and Stomatology Center in 2007 - 2017. 136 patients (93%) had de-fects of the bones of the facial skeleton and the skull calvarium. In other cases, there were defects of the clavicle (2 patients), defects of the femur (2 patients), defects of the humerus (2 patients), a defect of the radius (1 patient), a defect of the navicular bone (1 patient).
 Results. Flaps were used to close the defects in 87% of cases (125 patients), and alloplastic implants were utilized in 13% of cases (19 patients). Additive technologies were used in 85% (n = 123) cases for planning the operation to eliminate defects, as well as for manufacturing surgical models and templates. Clinical cases are considered as examples of the use of the additive technologies for planning and performing reconstructive operations to close bone defects of different locations.
 The incidence of postoperative complications in the group of patients with facial skeleton and crani-al vault bones defects who underwent surgical interventions using templates was 26%, including minor complications - 17.5%, large - 8.5%. Among minor complications, hematomas (5%) and sup-puration (5%) of the recipient wound prevailed, less often similar complications were hematomas (4%) and suppuration (3%) of the donor wound. Large complications were represented by cases of complete (4%) or partial (5%) transplant necrosis.
 During surgical interventions without a template, it took significantly longer than the average time of grafting and graft formation (212 ± 18.7 min) than during operations with a template, including with a guide for drilling (136 ± 12.6 min, p <0.001) and without a guide for drilling (160 ± 16.3 min, p <0.001).
 Conclusion. The use of surgical models and templates during reconstructive operations shortens the time of the operation and reduces the number of postoperative complications.

Innovative technologies providing enhancement of non-ferrous, precious, rare and rare earth metals extraction

The article provides the technologies of enrichment and metallurgy processing of mineral and man-made raw materials. New technical solutions are proposed to increase the end-to-end copper extraction, industrial products processing of copper production to obtain high purity selenium; extraction of gold from resistant mineral raw materials with the use of new reagents and equipment, processing of ferrous bauxite and alumina production waste, extraction of rare and rare earth metals from industrial products and wastes of chrome, phosphorus and uranium production, obtaining rhenium and Nickel-cobalt concentrate from the wastes of heat-resistant Nickel alloys. Innovative Bayer-hydrogenative technology of ferruginous bauxite processing was developed and tested using pilot facility. The technologies and equipment to produce a composite hydrogen permeable membrane based on niobium and obtaining castings of implants by casting method of titanium alloys with application of additive technologies were developed.

Assembly methods of solving inverse problems as an integral element of additive technologies for interpretations of gravity anomalies

In recent years, the theory of interpretation of gravitational anomalies has been replenished with fundamentally different from familiar, additive technologies for extracting information about the studied geo-density medium. The concept of «additivity» implies a summation in the results of the interpretation of information carried by each of the found admissible solutions to the inverse problem. At the same time, the results of the interpretation themselves are not expressed, as usual, in terms of one of these solutions. In the ore inverse problem of gravity exploration, an effective working tool for such technologies has become the assembly algorithms for constructing valid interpretation options. These algorithms have universal capabilities in the matter of accounting for a priori data and do not have high requirements for the formation of the initial approximation of the field source model, which is crucial from the point of view of their application in additive technologies. At the same time, all hitherto known modifications of the mounting method were designed for formulating inverse problems in which there are bodies with effective densities of the same sign. Due to the integration of the method with the procedure for separating gravitational fields, the problem of different sign densities was solved. The separation of the observed field into two components, due to the influence of sources with positive and negative effective density, is carried out by the approximation method. To approximate the discrete values of gravity, the sets of elementary sources under each point of observation are used. The masses of sources are determined by solving a system of linear algebraic equations. The sources are successively immersed at different depths corresponding to different variants of the selection of the interpreted field components. The article evaluates the current state and prospects for the further development of additive technologies for interpreting gravitational anomalies based on the methods that implement the concept of the mounting approach by V. N. Strakhov. Model of model examples are given illustrating the capabilities of the presented algorithms.

Measures for the Development of Medical Additive Technologies in the Russian Federation

Three-dimensional printing has several significant advantages over traditional methods of production: simplification and acceleration of the production process, versatility, low cost and a few others. As a result, additive technologies have quickly become a highly promising area with great potential in many areas of human activity, finding more and more points of application. Medicine is no exception. The development of three-dimensional printing in the field of medicine can not only solve a few pressing health problems, but also stimulate the progress of technology. To date, three-dimensional medical printing is used in the following areas: individual prostheses both temporary and permanent wear, surgical instruments, simulation manuals for training medical students and preoperative training of surgeons. Of interest is the joint application of additive technologies with cellular technologies – bioprinting. Despite its great potential, this activity is not sufficiently regulated, which is a serious obstacle to its development. The introduction into practice of the principles proposed in this work of the device and functioning of a specialized service – laboratory of additive medical production – should solve this problem and contribute to the rapid development of medical three-dimensional printing in the Russian Federation.

The Investigation of the Chemical Composition, Structure, and Mechanical Properties of EP648 Alloy at Different Stages of Additive Manufacturing

The chemical composition of a nickel heat-resistant alloy of the EP648 brand at different stages of additive manufacturing, as well as the structure and mechanical properties of the synthesized material in comparison with a material obtained via a traditional deformation method, is investigated. It is shown that the application of additive technologies in the manufacture of EP648 nickel heat-resistant alloy leads to a significant increase in the concentration of gases (O and N) in the alloy, formation of a fine-grain structure, and increased porosity. Here, an increase in the strength properties and a decrease in the impact strength, low cycle fatigue, and plasticity are characteristic of such a material. The time to failure of the synthesized specimens in a creep rupture test exceeds that of sheet specimens but is inferior to that of deformed bars.

Volumetric Reduction of the FeCl2–CaCl2 Melt by Calcium Dissolved in Calcium Chloride

The purpose of this study is to fabricate highly dispersed powder suitable for spheroidization with further application in additive technologies. The volumetric reduction of the FeCl2–CaCl2 melt by calcium dissolved in CaCl2 produced a fine iron powder. The process included three states, notably, the preparation of melts containing FeCl2 and Ca, their mixing, and high-temperature aging at 800°C for 1 h. Upon finishing the process, the solidified fusion cake is divided into top and bottom parts. The product from the top part has a specific surface of 7.60 m2/g, and that from the bottom part has a specific surface of 5.38 m2/g. The average particle size is 157 μm for the former and 124 μm for the latter. Ultrasonic dispersing is reduced to 26 μm and 71 μm, respectively. Quantitative X-ray phase analysis shows that the main phase of powder is metallic iron (more than 97 wt %). Thus, the originality of the research is due to the application of an intense volumetric reduction of iron from chloride melts by calcium dissolved in its chloride. The uniqueness of the study is due to its product, so far as the main part of reduced iron is arranged in the melt bulk in the form of linear aggregates 40–600 μm in length and 10–50 μm in diameter, which easily destruct by ultrasonic dispersal into separate crystals with an average size of 26 μm. The results of the study show the possibility of implementing the calcium-thermal production of fine iron powder.

Application of additive technologies and simulation systems in the preparation of molding production

Application of additive technologies and simulation systems in the preparation of molding production

Application of additive technology of selective laser melting (SLM) in designing a low emission combustion chamber of a gas turbine plant

The paper deals with the questions of introducing the additive technology of selective laser melting (SLM) into the production of the main structural elements of a combustion chamber for ground-based gas pumping, power and transport gas turbines. A fundamentally new design of a low-emission two-circuit burner was developed, adapted for the manufacture of products with a complex geometry through the use of selective laser melting (SLM) of metal powders according to mathematical CAD-models with the help of an advanced production technology. Technical difficulties associated with the implementation of additive manufacturing technology were overcome. The process chain was tried out from design to manufacturing and quality control of finished structural elements under conditions of mass production. The deficiencies of the parts manufactured by the additive technology were revealed and ultimately eliminated. Successful development of burners for a low-emission combustion chamber using a new technology significantly reduces labor intensity and time of production while maintaining high quality.

X-RAY DIFFRACTION ANALYSIS OF THE ADDITIVE PRODUCTS OF ELECTRICAL DISCHARGE MACHINING OF COBALT POWDERS

The main advantage of the technology of electroerosion dispersion is the use of waste as raw materials, which is much cheaper than the clean components used in traditional technologies. In addition, this technology is powder, which allows powder-alloys. The widespread use of the method of electroerosion dispersion for the processing of metal waste into powders for their reuse and application in additive technologies is constrained by the lack of scientific and technical literature full information on the effect of the initial composition, modes and medium on the properties of powders and technologies of practical application. Therefore, the development of technologies for the reuse of electroerosion powders and evaluation of the effectiveness of their use requires complex theoretical and experimental studies. The aim of this work was to carry out x-ray diffraction analysis of the additive products of electrical discharge machining of cobalt powders. For the proposed studies selected waste cobalt alloy brand CHMS "CELLET". Butyl alcohol (butanol-1) was used as a working liquid. To obtain the cobalt powders used for the installation of AED dielectric materials. Dispersion parameters: voltage 100 V, capacity 48 UF, pulse repetition rate 120 Hz. The phase composition of the samples was studied by x-ray diffraction using Rigaku Ultima IV diffractometer in Cu-Ka radiation (wavelength λ = 0.154178 nm) using Soller slots. According to the results of studies of x-ray diffraction analysis of additive products obtained from powders made by electroerosion dispersion of cobalt-chromium waste, it was experimentally established that the main phases in sintered samples are Co, Cr and Co 3 C.

Efficiency of Hybrid Cyclic Processing with the Use of Additive Technologies on CNC Machines for the Manufacture of Composite Aviation Parts due to the Reduction of Processing Errors

In this paper we consider the effectiveness of additive technologies for the technological preparation of production of shaped complex products. The aspects of application of additive technologies in diversified production cycles of enterprises are stated. The positive aspects of the use of additive technologies in the design development of technological cycles of complex products are considered. The need to reduce the weight and size of modern aircraft makes the developers of these systems apply increasingly new and innovative solutions in the field of product design and in the field of their direct production. Additive technologies allow to reduce the weight of the product, while maintaining all the characteristics laid by the designer. The paper considers a cyclic hybrid technology in the production of parts and elements of aircraft. Each cycle consists of direct laser growing of the working surface of the part and subsequent machining. The aspects of production of details from the point of view of ensuring the condition of unity of design and technological base are considered, and also the analysis of the errors of production excluded in the course of the offered technology arising at traditional cycles of production of such detail is carried out.