Основные проблемы внедрения методов переработки полимерных композиционных материалов и обеспечения технологических процессов при производстве морской техники

In connection with the permanent growth worldwide, including in the domestic aircraft industry, of the use of polymer composite materials in the structures of civil aircraft, the problem of analyzing the effectiveness of the use of composites at all stages of the life cycle of the corresponding structures becomes relevant. An engineering method for the implementation of qualimetry in the system of metrological support for the main stages of designing structures made of polymer composite materials in civil aircraft of the transport category, based on the use of integrated quality indicators and expert assessment of the characteristics of the main design stages, is proposed and justified. General key tables for the synthesis of significance levels of the main stages of designing composite structures for expert evaluation of the effectiveness of operations have been developed. The main (defining) principles of integral indicators of quality of the components of design levels are established. The reliance of experts on the main features of the quality indicators of the design stages ensures the minimization of errors in establishing the significance ranks of these stages. The decomposition of the classifier of the type "Design of aircraft structures from polymer composite materials" was carried out, which systematizes the analysis and synthesis of the main steps for implementing the proposed engineering methodology for qualimetric support for the design of aircraft structures from polymer composite materials, the sequence and implementation by an expert group.A criterion for the effectiveness of an engineering methodology for qualimetric support for the implementation of design stages has been implemented in the form of an additive model of the ratio of the effect of each design stage, expressed as the sum of quality indicators to the total cost of funds for its provision, taking into account the coefficient of significance of the indicators. A hypothetical example of the implementation of the proposed engineering methodology for analyzing the effectiveness at the initial stages of its development at an enterprise that predicts a promising increase in the volume of use of composites in domestic aircraft of the transport category and their modifications is given. The proposed engineering method for the implementation of qualimetry in the system of metrological support for the stages of designing composite structures of domestic aircraft, after practical testing and refinement in a specific production environment, can become an effective tool for increasing the effectiveness of predicting the growth in the volume of use of polymer composite materials in the domestic aircraft industry.

Based on the analysis of scientific and technical literature and trends in the development of multi-purpose aircrafts, we can see a steady extension of the use of polymer composite materials (PCM) in their design. The importance of lightning protection is noted for aircrafts, the skin of which consists mainly of the PCM, and it is shown that one of the common means is a lightning protection coating (LPC) in the form of a metal grid distributed in the PCM surface layer. Anisotropy of PCM properties and reduced fracture toughness in comparison with metals necessitates the improvement of PCM compositions and technologies of their formation as well as the development of methods for final hardening treatment in the cured state, which can be effectively performed under the effect of microwave electromagnetic field. Consideration is given to the influence of a short-term exposure to microwave electromagnetic field on the stability of carbon fiber-reinforced PCM with PLC against impact loads, as well as on the surface hardness. Our findings show a decrease in the damaged area of the impact zone by 40-60% and the absence of microcracking and delamination as well as an increase in hardness by 7.8%. Particular emphasis is placed on a 3-fold decrease in the spread of hardness values after the microwave exposure, this indicating a significant increase in the uniformity of this important characteristic for the component performance. As a mechanism of these modifications, it is proposed to reduce the pore size and porosity and to increase the number of points of contact interaction between matrix and fiber agglomerates that ensure an increase in the structural density.

It is shown that in the complex problem of permanent increase in the competitiveness of aircraft, a special role is played by the increasing use of polymer composite materials in aircraft structures of the transport category every year. An important role is played not only by the rational choice of structural and technological solutions of their units and assemblies, but also by the use of new composite materials to reduce the cost and production time of aircraft structures, which greatly contributes to the implementation of high flight technological and economic characteristics of competitive aircraft in the global market for sales and services. A review and analysis of the development of new composite materials and technologies for their processing into products, discussed at the annual international exhibition Sampe 2019. From an analysis of the results of the materials of the exhibition and conferences held within its framework, it follows that the global aviation industry is paying more and more attention to the study of structural thermoplastics and the development of new technological processes associated with these materials, in particular, welding. In the field of aircraft manufacturing, various companies and institutes are working to optimize and reduce the cost of production processes for parts from polymer composite materials, especially in the direction of autoclave-free production technologies. New developments of leading aircraft manufacturers, in particular AIRBUS, for the creation of large-sized responsible high-load structural elements of aircraft from polymer composite materials with a thermoplastic matrix are presented. Of particular note is 3D printing technology, which aircraft manufacturers have successfully begun to use for the manufacture of aircraft parts. It is noted that this technology allows not only to reduce the production cycle of manufacturing parts, but also significantly reduce the energy intensity of processes, which positively affects the cost of products. During a visit to the AIRBUS factory in Nantes, a high level of automation of production processes for manufacturing parts from polymer composite materials with a large number of laying, winding machines, CNC machines, robots was noted, which is due to a significant production program for the A350XWB and A400M aircraft with a high degree of automation of production processes, and also a very high level of safety and labor protection.

Currently, there is an intensive growth in the use of polymer composite materials in all areas of industry, which is due to their unique properties—high strength, lightness, corrosion resistance. In connection with the development of new technologies, there is a need to create a new class of environmentally friendly materials that provide efficient and cost-effective use of raw materials. This paper considers synthetic nanostructured aluminosilicates with a given Si / Al ratio of 1; 3; 5 as modifiers of polytetrafluoroethylene. The phase, elemental composition and thermal behavior of the synthesized compounds are studied. It was found that the use of aluminosilicates contributes to an increase in tensile strength by 40% and relative elongation at break by 70% relative to the original polymer matrix. The introduction of aluminosilicate is accompanied by an increase in wear resistance by 521 times. Thus, a new class of modifiers for polymer composite materials has been synthesized.

The development of scientific and technological progress in mechanical engineering, energy, aerospace and other industries is unthinkable without the creation of new structural materials that can improve the most important parameters of engines, machines and mechanisms, assemblies, devices and increase their mass performance, reliability, service life of products and reduce their material consumption. Products and aggregates from polymer composite materials (PCM) can be obtained in various ways. In industrial production, the most widely used method of winding and pressing. Pressing can be carried out using a mixture of preliminarily fiber and a polymer binder. One of the most promising methods of forming products and assemblies from a variety of plastic is the method of winding with fiber, due to the fact that it creates the required filler structure in the factories depending on their shape and operation characteristics. All areas of effective use of polymer composite materials are reflected. This article discusses the technological capabilities and applications of traditional and new varieties of the method. Even, the results of an analysis of the prospects for the development of manufacturing technologies for products and aggregates from polymer composite materials using the winding method are presented. There are methods of dry and wet winding. Consider these winding methods. Winding is carried out on a mandrel mounted on a machine with numerical control. This method is also called the spiral winding method. Existing approaches to the development of mathematical models are described and created for the manufacture of complex structural elements, including products and an assembly with a curved spatial axis, and so on.

The development of scientific and technological progress in mechanical engineering, energy, aerospace and other industries is unthinkable without the creation of new structural materials that can improve the most important parameters of engines, machines and mechanisms, assemblies, devices and increase their mass performance, reliability, service life of products and reduce their material consumption. Products and aggregates from polymer composite materials (PCM) can be obtained in various ways. In industrial production, the most widely used method of winding and pressing. Pressing can be carried out using a mixture of preliminarily fiber and a polymer binder. One of the most promising methods of forming products and assemblies from a variety of plastic is the method of winding with fiber, due to the fact that it creates the required filler structure in the factories depending on their shape and operation characteristics. All areas of effective use of polymer composite materials are reflected. This article discusses the technological capabilities and applications of traditional and new varieties of the method. Even, the results of an analysis of the prospects for the development of manufacturing technologies for products and aggregates from polymer composite materials using the winding method are presented. There are methods of dry and wet winding. Consider these winding methods. Winding is carried out on a mandrel mounted on a machine with numerical control. This method is also called the spiral winding method. Existing approaches to the development of mathematical models are described and created for the manufacture of complex structural elements, including products and an assembly with a curved spatial axis, and so on.

Background. This study systematizes the principles of using polymer composite materials in bridge structure design, outlining the fundamental principles for calculating load-bearing structures of bridge spans featuring these materials. Aim. The goal is to enhance the strength and durability of bridge spans during construction and maintenance, while optimizing costs through the use of polymer composite materials. Materials and Methods. The research employs a modern approach to bridge structure design, utilizing mathematical statistics for experimental data analysis and numerical methods for calculating bridge structures using nonlinear deformation models of anisotropic materials. Results. Developed principles for designing bridge spans with polymer composite elements include methods for strengthening and reinforcing concrete bridge structures. These methods account for operational factors such as long-term constant and temporary loads, low and elevated temperatures, as well as methods for designing all-composite spans pedestrian and road bridges Conclusion. The principles of designing bridge spans with elements made of polymer composite materials have been introduced into the practice of transport construction in the Russian Federation. The technical and economic efficiency of using polymer composite materials in bridge structures of transport infrastructure has been confirmed.

The analysis of both foreign and domestic experience in the use of polymer composite materials in the structures of the lifting surfaces of a helicopter (blades, wing, stabilizer, fin), as well as the technological features of the manufacture of such structures is performed. The design and technological and operational advantages and disadvantages of composite blades compared to all-metal blades are noted. The load-carrying structures of the composite main rotor blades of a helicopter, as well as the schemes of special joints of the MR blade and the polymer composite materials package are considered. The route scheme for manufacturing of the composite blade of a helicopter is presented. The technological features of manufacturing the composite spar of a blade are analyzed by the methods of lay-up and winding-on. The scheme and route technology for manufacturing the tail section of a blade, including the scheme of lay-up and molding of composite covers and ribs, are presented. The efficiency of the equipment for automatic cutting of the roll prepreg and manual lay-up of the prepreg layers with the help of a laser projector is noted. The technological tasks of special software for lay-up CNC equipment are given. The technological transitions of the general assembly-bonding of a helicopter composite blade in the assembly jig are presented. Recommendations are given on the method of manufacturing a monoblock lifting surfaces of type of a wing, tail pylon and helicopter stabilizer from polymer composite materials using automated winding-on. A scheme of surface reinforcement is proposed. It allows to obtain a variable wall thickness from the root rib to the end rib. The trajectories of movement of the working bodies of a three-coordinate CNC winding machine for their implementation are determined. A variant of a computer simulation of the stages of lay-up of a reinforcing tape on a technological mandrel is shown. The technology of manufacturing a low aspect wing made of polymer composite materials by the method of automated winding is presented.

The paper deals with the experience of using polymer composite materials (PCM) in shipbuilding. There are presented samples of ship structures designed using PCM. A number of modern Russian and foreign projects in the military and civil shipbuilding are considered. The main advantages of PCM in comparison with other materials used in shipbuilding are indicated. Due to the mechanical and other characteristics of PCM, the approach of the Russian Maritime Register of Shipping (RMRS) to the possibility of using PCM for individual ship structures was changed. There have been analyzed the main technological qualities, according to which PCM tests are carried out to select the area of their application. The trends in the development of production and methods for the manufacture of PCM are appointed. The material presented demonstrates the pace of introduction of new methods into the PCM manufacturing. There has been conducted the analysis of the characteristics by which the development of new regulatory documents for the certification and acceptance of PCM is carried out. In the laboratories of Astrakhan State Technical University there are carried out the tests on using PCM for manufacturing the ship structures. The materials presented show the expansion of PCM application area and using the new methods in shipbuilding.

For a number of years, there has been a continuous increase in the use of polymer composite materials (PCM) in products of aviation and space technology. Modern multifunctional thermoanalytical complexes equipped with computer technology are essentially mobile laboratories. They are able to solve a wide variety of materials science and technological problems, both in applied scientific research and in quality control of products supplied to manufacturing enterprises. Using the example of experimental data obtained during the study of the curing processes of thermosetting semi–finished products (prepregs) of polymer composite materials (PCM), the methodological capabilities of modern devices for thermal analysis - differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and thermomechanical analysis (TMA) are shown, allowing to investigate and predict changes in the technological properties of prepregs in a wide range temperatures.

The article justifies the need for technological solutions in the use of polymer-composite materials in order to limit the impact of dynamic frictional forces in oil drilling. The relationship between macrostructural surfaces was investigated, in particular increasing the effectiveness of the axial load on the drill bit during drilling directional and horizontal wells. It is established that the polymer coating of drill string elements (BC) based on fluoroplastic brand F-4, with a small thickness of 2 ? 3 mm and the appropriate application technology provides high physical and technical characteristics of this coating and under operating conditions has a low coefficient of wear on large functioning friction, which is about 4 ? 7.5 km. The surface of the drill string, covered with a polymer coating, in the trapped areas, with a low coefficient of friction (~ 0.025) is not capable of trapping. To reduce friction forces, the use of polymer-composite materials (PCM) to cover the surface of the elements of the drill string is proposed. Methods and mathematical models are given, due to which it is possible to obtain PCM with predetermined physical and mechanical properties that would meet the requirements of the operation of drill columns during drilling of inclined and horizontal wells. The obtained results of laboratory, analytical and industrial researches guarantee increase of efficiency of adjustment of axial loading on the rock-destroying instrument influencing mechanical speed of drilling.

Additive manufacturing (AM) technology is nowadays one of the advanced manufacturing technologies used to convert three dimensional product data to physical objects without any special tooling. The emergence of the technology has made production of complex geometries having consumer demands for more customized products and services. Though the underlying technology was initially intended for rapid prototyping, the technology has recently getting wider attention in diverse industrial sectors using different material types commonly polymers, metals, ceramics, and other compatible researched materials as input. Because the technology processes the input materials with no or very low wastes, the use of polymer composite materials leads to a no waste manufacturing system. This article aims to review and analyse the opportunity and existing challenges for AM technology in processing polymer composites and provide an insight on the state-of -the art applications. The paper provides an overview of the materials and processes currently available for this novel production technology to fill the industrial needs for engineering application. In addition, closely reviewing published research works in the area, the existing research gaps are identified for possible future research in the field.

This article addresses the issue of determining the ability of marine diesel oil to penetrate into the structure of a composite material made with reinforcing glass fabrics and a polyester binder. The penetration capability is assessed by measuring the weight change of samples cut from a standard plate of polymer composite material before and after immersion in a container with marine diesel oil for a specified duration. A low penetration rate of diesel oil into this material has been established, depending on its structure—specifically, on the arrangement of reinforcing materials and whether or not the edges were treated with polyester resin after cutting from the standard plate. The mechanical properties (tensile, compressive, and flexural strength) of the composite material after removal from diesel oil are reported. This study also examines how processing the ends of cut samples with polyester resin affects marine diesel oil penetration into polymer composite structures. The influence of sample layering (glass wool and roving fiberglass) in a liquid medium (diesel oil) on mechanical characteristics during bending, stretching, and compression is analyzed. The article presents research findings that demonstrate a direct correlation between ultimate strength, breaking force, and the number of roving layers in polymer composite materials treated with polyester resin. Experimental results reveal how diesel oil penetrates composite materials, altering their mechanical properties upon immersion in a liquid medium. Findings from an experimental study on various reinforcement schemes confirm the feasibility of using these materials in ship hull structures. Specifically, these materials are recommended for manufacturing marine tanks designed for storing diesel oil.

Monitoring of FRP Strengthened Concrete Structures Using FBG Sensors

Numerous studies of road surfaces in the areas of deformation joints of bridges and overpasses have shown that the use of polymer composite materials can significantly reduce cracks and destruction. The cyclic durability of such materials prevents rutting in the zone of deformation seams, due to their damping properties. Effective building materials based on furfural acetone monomers (FAM) are used for the manufacture of tides that experience cyclic impacts of vehicle wheels. Therefore, tests were conducted on the endurance of FAM polymer concrete under the influence of cyclic application of load. Today cyclic and static durability of traditional FAM polymer concretes has been studied in detail. However, the carcass technology can improve the characteristics of polymer concrete, in particular, reduce shrinkage. These polymer concretes are produced in two stages. First, a carcass is created from the filler grains glued together, and then the voids are filled with a matrix composition. This article presents the results of endurance tests of polymer concrete made using carcass and traditional technologies, with the same set of raw materials. To determine the limit of endurance, we used the method of planning an experiment with the construction of an orthogonal-composite plan of the second order. The cycle asymmetry coefficient and loading level (as a percentage of the destruction load) were selected as variable factors affecting the cyclic durability. Lines of fatigue strength of traditional polymer concrete FAM and obtained by carcass manufacturing technology at different values of the cycle asymmetry coefficient are also constructed. The results of endurance tests under the influence of repeated application of load showed that the polymer composite material based on furfural acetone monomer, obtained by carcass technology, has an increased cyclic durability compared to traditional polymer concrete.