Modern Composite Materials Research Articles

Color stability of composite materials to food colorants: A laboratory study

BACKGROUND: Maintaining the esthetic characteristics of direct composite restorations for a long time is relevant. The color stability of food colorants is an important esthetic characteristic of a composite material. Comparative information about the color stability of modern composite restorative materials and recommendations based on optimal clinical results for direct composite restoration are of interest.
 AIM: To compare the color stability of modern composite restorative materials with the most common food colorants in laboratory conditions.
 MATERIALS AND METHODS: The color stability of modern restorative materials, namely, Restavrin (Technodent, Russia), GrandioSO (VOCO, Germany), Harmonize (Kerr, USA), Charisma Classic (Kulzer, Germany), Filtek Z250 (3M, USA/Germany), and Estelite Asteria (Tokuyama, Japan), were assessed. Black coffee, black tea, carbonated soft drink cola, dry red wine, and cognac were used as coloring solutions. The samples were exposed for 14 days, and the temperature was 37 C. The control solution was distilled water. Vita Easyshade Advance 4.0 spectrophotometer was used. The average deviation of the color of the studied samples from the reference indicators (∆E), total color stability of the studied materials ( ∆Em), and coloring potential of different coloring solutions in relation to composite materials ( ∆Ec) were determined.
 RESULTS: The deviation of the color of the studied samples of composite materials from the reference indicators (∆Е) depending on the coloring solution was assessed. The total color stability of the studied materials in relation to food colorants ( ∆Em) as this characteristic deteriorates was as follows: Estelite Asteria, 8.640.08; Harmonize, 10.300.14; Restavrin, 12.300.12; GrandioSO, 12.960.10; Charisma Classic, 13.940.14; and Filtek Z250,15.820.15. The most aggressive food colorants with respect to composite restorative materials were black coffee ( ∆Ec=20.080.12), dry red wine ( ∆Ec=19.180.10), and black tea ( ∆Ec=18.54 0.15).
 CONCLUSION: Information about the color stability of composite materials in relation to food colorants allows planning the restoration of teeth located in an esthetically significant area, taking into account the eating habits of patients.

Structure and Properties of Ti3AlC2-SiC and Ti3AlC2-TiC Materials Obtained by Powder Injection Molding Technology

Powder injection melting (PIM) and material extrusion additive manufacturing (MEAM) are promising production technologies that allow us to obtain products from modern composite materials. These technologies make it possible to obtain products of complex shape from ceramic composite materials, which is a non-trivial task. A highly filled polymer feedstock is used as a source material in such technologies. In this work, a study of the structures and properties of samples obtained from SiC-Ti3AlC2 and TiC-Ti3AlC2 feedstocks by the PIM method was performed. The main purpose of this work was to study the influence of the powder compositions in feedstocks on the rheological properties and the structures of the obtained samples, as well as to determine the sintering parameters of samples of these compositions. In the future, it is planned to use the received and studied feedstocks in material extrusion additive manufacturing (MEAM). It was found that the investigated compositions had different MFI values depending on the composition. The effect of the sintering parameters on the structure and properties was shown. During the sintering of SiC-Ti3AlC2 ceramics in the temperature range of 1200–1400 °C in a vacuum, the main components of the mixture interacted with the formation of Ti3SiC2 and TiC. For materials of the TiC-Ti3AlC2 composition, partial oxidation of the material and the formation of titanium and aluminum oxides was observed.

Experimental monitoring of vibrations and the problem of amplitude quantification

Experimental monitoring of blade vibration in turbomachinery is typically based on blade-mounted strain gauges. Their signals are used to derive vibration amplitudes which are compared to previously determined modal scope limits, including a safety factor. According to industrial guidelines, this factor is chosen conservatively to ensure safe operation of the machine.For the experimental campaign with the open test case fan ECL5, which is representative for modern lightweight UHBR architectures, it is planned to conduct measurements close to the stability limit. These investigations require a close approach to the limit and hence demand for accurate quantification of vibration amplitudes to ensure secure operation without exhaustive safety margins. It is required that the surveillance is possible in real time and not only in post-processing.Historically, short-time Fourier transformations of vibration sensors are used, but the complex nature of coupled phenomena near the stability limit has an influence on the amplitude accuracy, depending on evaluation parameters. This was demonstrated in a previous study using fast response wall pressure transducers. The present study investigates the influence on blade vibration data of a modern composite material transonic fan. Different methods are compared, sensitivity to evaluation parameters is analyzed and guidelines are given for fast and robust surveillance of critical vibration modes.

Problem of plane strain state of two-layer body in dynamic elastic-plastic formulation (Part III)

Composites materials are artificially created materials that consist of two or more components that differ in composition and are separated by a pronounced boundary. The development of modern composite materials is associated with the discovery of high-strength whiskers, with the study and use of aluminides and high-strength alloys. At present, various composite materials have been developed and used: fibrous; reinforced with whiskers and continuous crystals and fibres of refractory compounds and elements; dispersion-hardened materials; layered materials; alloys with directional crystallization of eutectic structures; alloys with intermetallic hardening. There are many technologies for producing composites: imbibition of reinforcing fibres with matrix (base) material; cold pressing of components followed by sintering; sediment of the matrix by plasma spraying on the hardener, followed by compression; batch diffusion welding of multilayer tapes of components; joint rolling of reinforcing elements with a matrix, and etc. The use of composites makes it possible to reduce the weight of aircraft, cars, ships, increase the efficiency of engines, and create new constructions with high performance and reliability. The development of composites with high impact resistance is an important direction in the industry. The strength characteristics of a layered composite material are decisive under shear loads, loading of the composite in directions other than the orientation of the layers, and cyclic loading. In this paper, we study the non-stationary interaction of an absolutely rigid body on a two-layer reinforced composite material. The action of the striker is replaced by a non-stationary vertical even distributed load, which changes according to a linear function, in the area of initial contact, which is assumed to be unchanged over time. In contrast to the previous articles (Parts I and II), in this papers there is an investigation of the strain-stress state, the fields of the Odquist parameter and normal stresses depending on the material of the first (upper) layer.

Review of modern ceramic cellular materials and composites used in heat engineering

THE PURPOSE. Cellular ceramic materials and composites have found application in many industries: energy, chemical industry, construction, aerospace. Due to their high thermomechanical properties, resistance to high temperatures and low density, cellular ceramic materials are widely used as heat exchangers for heat recovery from exhaust gases of gas turbine engines, combined-cycle plants, industrial furnaces, etc. The purpose of this work is to review modern cellular ceramic materials and composites used in heat engineering and having different structure, properties and chemical composition.METHODS. We have carried out a broad review of the literature on ceramic cellular materials and composites. We studied both domestic and foreign literature.RESULTS. The analysis of cellular ceramic materials with a regular (lattices) and random (foam) structure has been carried out. The main factors influencing the properties of ceramic foams and lattices are analyzed. Also, the main methods for the production of ceramic materials were studied, their advantages and disadvantages were revealed. A review of modern composite materials based on a ceramic matrix reinforced with carbon nanotubes, graphene nanoplates, and carbon fibers has been carried out.CONCLUSION. The properties of ceramic cellular materials, as well as their areas of application, depend on the production methods and the structure of the material. Open-cell foams are used as filters, heat exchangers, while closed-cell foams are used as thermal insulation. Applications for ceramic lattices are limited by the precision, resolution, and size of 3D printing. Thus, the improvement of additive manufacturing technologies will improve the characteristics of ceramic gratings and expand their areas of application.

Testing of Damaged Single-Bay Reinforced Concrete Frames Strengthened with Masonry Infill Walls

Despite achieving consensus and having current knowledge on the behaviour and contribution of masonry infill walls, there remain unresolved issues regarding their nonlinear behaviour as a method for strengthening existing reinforced concrete (RC) frames with effective modifications, primarily infills and the interconnection of infills and frames. The challenge for safely and economically designing frames with competent walls is to utilise the stiffening benefits while ensuring that the increased lateral forces and reduced drift capacity do not hinder performance. This study aims to investigate the potential of using masonry infill to strengthen previously slightly damaged RC frames. Experimental tests were conducted on previously slightly damaged RC frame specimens infilled with vertically hollowed-clay and solid-clay masonry units, connected to the frame elements using traditional methods (i.e., avoiding the use of modern composite materials). These strengthened infilled frame structures were subjected to constant vertical and cyclic lateral loading, which revealed improved stiffness, strength, and damping characteristics, enhancing their overall behaviour. As the main novelties, the study found that when damaged RC frames were strengthened with masonry infill walls, their performance resembled that of undamaged infilled RC frames. The strengthened infilled frame structures exhibited enhanced stiffness, strength, and hysteretic damping. The increase in stiffness was observed regardless of the type of masonry units and the strengthening technique employed. However, the improvements in strength and hysteretic damping were influenced by the specific masonry units, particularly their robustness, and the chosen reinforcement method.

Preliminary Studies into Cutting of a Novel Two Component 3D-Printed Stainless Steel-Polymer Composite Material by Abrasive Water Jet.

Composites are materials with a heterogeneous structure, composed of two or more components with different properties. The properties of composites are never the sum or average of the properties of their components. There is a lot of research and many models on the different property assessments of composite materials. Composites are used as construction materials in key areas of technology, including in civil and mechanical engineering, aviation and space technology, and others. This work presents a modern composite material created with 3D-printing technology using the SLM method, and the possibility of its processing with one of the advanced manufacturing technologies, i.e., the Abrasive Water Jet (AWJ). Tests planned using DoE methods were carried out by changing control parameters such as the pressure, abrasive flow, and traverse speed. As a dependent parameter, the surface roughness parameter Sq (squared mean height) was selected and measured in different places of the cut composite. Based on the S/N ratio, the most favorable control parameters of the cutting process were also determined to achieve the lowest roughness of the cut surface. A clear effect of the controlled cutting process on the surface roughness was observed, as well as roughness variation for the metal and polymer component. In addition, the contact surface of the polymer with the metal in the cut zone was analyzed. Analysis of the contact surfaces on the microscope showed that the gap between the polymer-metal contact surfaces does not exceed 2.5 μm.

ОГЛЯД ПЕРСПЕКТИВ ЗАСТОСУВАННЯ СМУГ ВИГОТОВЛЕНИХ ЗА ТЕХНОЛОГІЄЮ FIBERGLASS ДЛЯ АРМУВАННЯ АРХІТЕКРУРНО-ДЕКОРАТИВНИХ ВИРОБІВ З ПРИРОДНОГО КАМЕНЮ

Purpose. The purpose of this study is to assess the feasibility of using fiberglass strips manufactured with technology for reinforcing architectural decorative products made of natural stone by comparing their strength properties and behavior under bending strength. Methodology. The preparation of samples for strength testing has been carried out, and recommendations regarding the process have been described. Recommendations have been provided regarding the preparation, configuration, and implementation of the main tools and materials involved in the course of the research. Components of the experiment aimed at determining the strength characteristics of the samples have been developed and described. In accordance with the set tasks and the array of data obtained empirically, numerical values of the strength characteristics of natural stone products under external loads have been calculated. The calculations are performed in accordance with the general principles of theoretical and applied mechanics. Results. The influence of reinforcement on the strength of stone has been studied, expanding existing theoretical knowledge about the strength properties of stone and the possibilities for their improvement. New theoretical models and methods for assessing the strength characteristics of stone, taking into account the influence of reinforcing elements, have been developed, contributing to a deeper understanding of the processes occurring in the structure of stone during reinforcement. Scientific novelty. The existing methods of reinforcing natural stone products have been systematized and reviewed, and the ways to optimize them using modern composite material manufactured with fiberglass technology have been suggested. The feasibility of applying internal reinforcement technology to enhance the strength properties of natural stone products has been substantiated. For the first time, the methodology and effectiveness of applying internal reinforcement manufactured with fiberglass technology to improve the strength properties of products from the Pokostiv deposit granodiorite have been analyzed. Practical significance. The practical importance of the obtained results lies in the opportunity to transform theoretical knowledge into practical recommendations for improving the technology of manufacturing products from natural stone to enhance their reliability in operation and simplify the manufacturing process.

Effect of Thermochemical Boronizing of Alumina Surface on the Borate Crystals Growth and Interaction with Nickel and Nickel Alloy

Wettability at the metal-ceramic interface is highly important for the development of modern composite materials. Poor wettability by metal melts restricts the use of alumina in protective metal matrix composite (MMC) coatings. In the present experimental study, the possibility to modify wetting properties of alumina by thermochemical surface boronizing was investigated. The results of SEM, EDS, XRD and XPS characterisation of surfaces revealed the formation of oxygen containing Al–B compounds identified as aluminium borates (Al18B4O33/Al4B2O9); no signs of non-oxide Al–B compounds were observed. The shape of the single splats deposited on the boronized alumina surface by the thermal spray and re-melted in the furnace revealed that significant wetting improvement by self-fluxing nickel alloy did not occur. However, the improvement of adhesion between the nickel/nickel alloy and Al2O3 surface was obtained due to formation of an intermediate layer consisting of B, O, Al and Si between the metal and ceramic surfaces at the presence of some silicon at the modified surfaces. The presented study demonstrates that the thermochemical boronizing of alumina in amorphous boron medium is a simple method to obtain a thin aluminium borate layer consisting of oriented nano-rod-like crystals, whose growing direction is predetermined by the orientation of the alumina grains’ faces at surface.

Assessment of the technical condition of cave complexes

The study of artificial caves and underground complexes, as well as their protection and preservation, remains a pressing problem of modern scientific research. Ancient dungeons, which are located not only in the territories of major cities (mainly in places where there were castle fortifications, trading rows, and monasteries), but also in small towns, cities, and villages, are in unsatisfactory condition. The work is devoted to the analysis of cave complexes and underground premises for historical purposes. Special attention should be paid to the operating conditions. The methods of surveying underground premises are given, in particular, attention is paid to the creation of 3D models. The results of the study of brick on water absorption result. The article pays attention to methods of strengthening damaged structures in operation conditions with modern composite materials based on basalt and carbon fibers

Jeffery's orbit leading to the foundation of flow-induced orientation in modern fiber composite materials

• Understanding the microstructure of flow-induced orientation distribution within fiber-reinforced thermoplastics composites is crucial for the current automotive and aerospace industries. • In the 100th anniversary of G.B. Jeffery's contribution, one therefore emphasizes that the Jeffery equation is important for basic flows to describe the flow-induced fiber orientation. • During a complex flow, it is significant to show that the shell-core microstructure of fiber orientation is related to characteristic shear rate and extension rate profiles. • Under the 3D-FRT injection molding simulation and the objective fiber orientation model, the predicted microstructure almost matches the related experimental data. On pursuing the seminal work of Jeffery's orbit (1922), the pioneering rheologists were inspired to originate modern suspension rheology in a fiber-filled viscous fluid. Understanding the flow-induced orientation distribution within fiber-reinforced thermoplastics (FRT) composites is crucial for the current automotive and aerospace industries. In the 100th anniversary of G.B. Jeffery's contribution, one therefore emphasizes the overview of advanced fiber orientation models studied on the suspension rheology. Herein the Jeffery equation is used in basic flows to describe the flow-induced fiber orientation. During a complex flow, it is significant to show that the shell-core microstructure of fiber orientation is related to characteristic shear rate and extension rate profiles. Under the 3D-FRT injection molding simulation and the objective fiber orientation model, the predicted microstructure almost matches the related experimental data. Additionally, numerous fiber vectors are visualized to exhibit the flow-induced orientation distribution.

Fast Statistical Homogenization Procedure for estimation of effective properties of Ceramic Matrix Composites (CMC) with random microstructure

The modern polycrystalline composite materials have a complex internal structure consisting of different phases and interfaces with random distribution. Relevant examples are Al2O3/ZrO2, i.e. alumina/zirconia composites, widely used as structural materials with applications ranging from aerospace to bio-engineering. Depending on the phases content and on the grain size a broad range of material characteristics, among which elastic constants, can be obtained.With the aim of characterizing this class of materials, we exploit a numerical Fast Statistical Homogenization Procedure (FSHP) in order to both estimate the size of the Representative Volume Elements (RVE) and the effective elastic properties, assuming a linear elastic material behaviour.The 2-D analyses are performed considering a microstructure inspired by images of real portions of the Al2O3/ZrO2 composite obtained from a scanning electron microscope. The recent Virtual Element Method is used in combination with the FSHP approach to numerically solve boundary value problems. Different volume contents of phases are considered ranging from pure Alumina to pure zirconia. The results are useful to reliably characterize such materials in the elastic range taking into account the role played by random distribution of grains.

ANALYSIS OF RESEARCH APPLICATIONS OF COMPOSITE TAPE FOR REINFORCEMENT OF WOODEN STRUCTURES

In the XXI century, the construction industry is developing at a rapid pace. Competitors of the same material, but reduced in cross-section by strengthening them with composite materials, compete with large-sized structures.
 Composite materials are considered to have relatively new operational and physical-mechanical properties, which are created due to the joint work of two or more components that differ in structure, chemical composition, physical and mechanical characteristics. One of the first composite materials is considered to be reinforced concrete, which was widely used in the late XIX century. At the beginning of the XX century for the needs of shipbuilding, aviation, aerospace, etc., modern composite materials such as fiberglass, consisting of artificial continuous glass fibers and artificial polymer matrix invented by A.K. Burov and his colleagues in the 30s of last century [1]. During the Great Patriotic War, fiberglass plates were used instead of aluminum in aircraft construction. In the 1960s, carbon fiber was developed in the United Kingdom and boron in the United States, which gave impetus to the development of a new generation of composite materials with high modulus of elasticity and high strength, which significantly increased their scope. .
 It can be noted that most composite materials are well resistant to many chemical influences: alkalis, acids, chlorides, sulfates, nitrates and others. All of them are not dangerous to human health in normal operation with the use of personal protective equipment in the direct performance of reinforcement work. This allows them to be used both in industrial and agricultural construction where there is a direct impact of the external environment on the structure reinforced with composite materials, and in residential buildings without harm to residents.
 After analyzing the creation and use of composite materials to strengthen structures of different materials, as well as methods of their application and physical and mechanical properties, it is assumed that such materials can be perfectly combined with solid and glued wood structures, increasing load-bearing capacity while reducing their cross section.

Experimental Investigation on RC Columns Confined by Jacket with Geopolymer Adhesive

Columns are one of the important structural members of engineering buildings. The impairment of reinforced concrete columns is one of the important problems affecting most structures, therefore the confinement of columns by fiber-reinforced polymers (FRP) is necessary to improve its behavior such as its load capacity, compressive strength, and ductility. The FRP used in the confinement is modern and wide application composite material in the field of civil engineering, which is pasted by epoxy. The fast impairment of epoxy at high temperatures leads to its replacement with an effective adhesive: geopolymers. This study presents the test result of an experimental investigation on confinement of six square RC columns with dimension (100*100*600mm) with geopolymer jacket under axial load conditions. The parameter considered is the jacketing material used (carbon fiber, plastic mesh, steel wire mesh, jute fiber, glass fiber mesh). Results of the test showed that confinement could improve the stiffness of the column by using a different type of material. The confinement with a carbon fiber reinforced geopolymers jackets can enhance the strength of the column after applying axial loading and improvement the performance of columns, but it is expensive. Where the increase in the load improvement and deformation capacity was (1.59 and 1.97), respectively, and the most effective jacket material in terms of economic cost and best performance in confinement operation consisted of (plastic mesh and steel wire mesh) compared to other types of material, with load enhancement by (1.41 and 1.27) and deformation capacity by (1.86 and 1.50), respectively compared with unconfined RC columns. Finally, the confinement by a different type of fiber-reinforced geopolymer adhesive is the most effective and used in the repair and rehabilitation of RC in the area with high-temperature climates.

The Influence of Tuff Particles on the Properties of the Sintered Copper Matrix Composite for Application in Resistance Welding Electrodes

This paper presents modern copper-matrix composite materials in which volcanic tuff particles are used as a reinforcing phase. The aim of the research was to determine the optimal shares of volcanic tuff additive based on such criteria as softening temperature, relative density, electrical conductivity, and hardness. The properties of the produced and tested composites allowed us to determine the usefulness of this type of material for resistance welding electrodes. To confirm the assumptions made, preliminary investigations of the durability and behavior of electrodes made of the tested material during the processes of welding non-alloy steel sheets were carried out. As a result of the research, it was discovered that the addition of 5% tuff produces the best results in this type of composite. It was found that for the sample with a 5% share of tuff, a high softening point above 600 °C was obtained, high hardness after densification at the level of 62 HRB, and high relative density of approximately 95% and very good conductivity at the level of approximately 45 MS/m. The conducted tests did not show any electrode wear different from the commonly used alloys for resistance welding.

Application of deep neural network learning in composites design

A timely review is presented on artificial intelligence (AI) and, more specifically, deep learning, which is a subfield of machine learning (ML), applied to the design and behaviour of modern composite materials systems. The use of composites is increasing due to their high specific strength and stiffness, which make them comparable to metals, and their tunable properties that can be altered to produce lightweight materials with efficient structural configurations. Recent studies are examined and discussed, wherein computational tools have been developed that mimic human brain activity to answer questions and solve challenging problems toward characterizing materials behaviour and improving the performance of materials with less effort and cost. The attractiveness of AI comes from its self-learning capability, the faster computer processing time of large datasets, and the potential to yield highly accurate results. However, as a data-driven method, the quantity and quality of data largely affect the accuracy of ML in addition to the need for well-designed AI algorithms and virtual reality models, hence the need to continue the research efforts in this area.

Graphene-based Nanocomposites for Automotive and Off-highway Vehicle Applications: A Review

Abstract: Abstract Abstract: Nanocomposites comprised of a polymer matrix and various types of nanosized fillers have remained one of the most important engineering materials and continue to draw great interest in the research community and industry. In particular, graphene in nanocomposites that possess high thermal conductivity and excellent mechanical, electrical, and optical properties have turned out to be promising fillers for making the next generation of advanced high-performance materials. Though large-scale production of graphene-based nanocomposites is a bit challenging due to the mechanical, functional, and interfacial properties of the graphene and polymer matrix under severe loading conditions, the automotive and off-highway machinery industries are expected to utilize the most modern composite materials, such as graphene-based nanocomposites, to create lighter, stronger, safer, and more energy-efficient cars in the future. Graphene-based material strategies have been investigated and demonstrated to be effective for structural applications in various industries, including electronics, electromechanical, and energy systems. However, currently, there is only limited research highlighting the specific knowledge available for design engineers and researchers involved in providing lightweight but strong solutions using graphene-based materials for automotive and off-highway vehicle applications. The present review presents an overview of the latest studies that utilize graphene-based nanomaterials and their composites in automotive and off-highway machinery applications. First, the paper describes the concept of traditional composites used presently in the engineering industries by considering its advantages and limitations. Then, it highlights the key benefits of using nanostructured carbon materials, such as graphene, through some recent studies available in the literature. Subsequently, it depicts the various mechanisms of integrating graphene as polymer reinforcements within the composite materials based on the survey and their related modelling, designing, and manufacturing capabilities suitable for the automotive and off-highway machinery industry. Finally, it outlines the available experimental evidence for graphene-based composites. To lay the groundwork for future work in this exciting area, the paper discusses the current challenges as well as future prospects in the field.

Tension system design based on heated-mandrel winding process

Heated-mandrel winding is the main process of modern composite material molding because of its characteristics of winding and curing in one step. Winding tension is a key factor in the molding process and has an important impact on the molding effect. Excessive winding tension will cause the inner looseness and outer tightening, and too small winding tension will cause the outer looseness and inner tightening. In short, the stratification will occur during the curing as long as the winding tension value is not set properly, which will seriously affect the molding quality of composite materials. The tension system of single winding process is difficult to apply to the heated-mandrel winding process because winding and curing are separate in the traditional single winding process, there is no need to consider the diversification of parameter state caused by curing reaction in winding process. In the heated-mandrel process, the balance of forces between adjacent layers is broken, the stress changes in adjacent layers affected by the temperature field are considered during winding. The tension values are obtained by adopting the tension system model established in this paper and the traditional finite element iterative search calculation method is replaced by numerical analysis method. An analytical algorithm for the method of winding with tension as the interference fit of the thin layers is adopted in the calculation procedures and the nonlinear tension solution problem is converted into a linear displacement-stress calculation problem. The lengthy and complicated traditional tension calculation method is simplified.

Quality factor as a tool to measure concentration and orientation of ferromagnetic fibres in sample

Fibre-reinforced concrete is a modern composite material. Steel fibres are often used as scattered reinforcement in cement composites. We can achieve anisotropic final products by orienting the fibres, i.e. higher strength in the required direction. One of the ways, how to control the orientation of ferromagnetic fibre in composites, is a non-destructive method based on mutual induction. The advantage of non-destructive testing is, among other things, the possibility of application to fresh cement mixtures. This paper presents a fast and effective non-destructive measuring method of fibres orientation degree and fibre volume in cementitious composites. Furthermore, the measurement of fibres oriented at different angles and different fibre volumes is shown.

ДОСЛІДЖЕННЯ ДОЦІЛЬНОСТІ ЗАСТОСУВАННЯ СКЛОПЛАСТИКОВИХ ТА БАЗАЛЬТОПЛАСТИКОВИХ СТЕРЖНІВ ДЛЯ АРМУВАННЯ ВИРОБІВ З КАМЕНЮ

Purpose. The purpose of this work is to study the feasibility of using different types of composite materials for natural stone products reinforcement by comparing their strength characteristics. Methodology. Recommendations for the preparation of samples for strength research have been implemented and described. Recommendations for the preparation, adjustment and commissioning of fixed assets and materials used in the study are given. The constituent elements of the experiment aimed at determining the strength characteristics of the samples are developed and described. Based on the results of the obtained data, the values of the basic strength parameters during the destruction of the samples under the action of bending loads have been calculated. Results. The study of the technology of stone products reinforcement allows solving a number of problems related to improving the quality and competitiveness of stone manufacturing. A holistic and scientifically sound study of reinforcement technology allows an array of empirical data and developing the optimal order of its use. Scientific novelty. Systematization and review of existing methods of natural stone products reinforcement are performed and methods of their optimization with the help of modern composite materials are offered. The expediency of using fiberglass and basalt-plastic composite materials for the purpose of reinforcing stone products has been empirically investigated. The expediency of using fiberglass and basalt-plastic composite materials for natural stone products reinforcement by comparing the obtained values of strength characteristics has been substantiated. Practical significance. The practical significance of the obtained results lies in the possibility of their application in order to simplify, modernize and improve the technology of stone products reinforcement for its widespread introduction as one of the basic technologies in the conditions of stone processing enterprises. However, the research results confirm the fact of the expediency of using composite reinforcement (especially basalt-plastic) to improve the strength properties of stone products.