Розробка та дослідження політетрафторетинових композитів триботехнічного призначення з активованими інгредієнтами

The influence of mechanochemical activation of matrix, fillers of various nature and composition on the structure and operating properties of polytetrafluoroethylene composites was explored. The effect of technological parameters of the process of mechanical activation on the structure, physical, mechanical and tribotechnical properties of polytetrafluoroethylene-based composites was examined.We established the modes of mechanic activation equipment for the preparation of matrix and fillers that provide for the maximum wear resistance of the composite while maintaining sufficient level of strength and we designed antifriction composites based on polytetrafluoroethylene of a new generation.Special features of developed technology for the production of composite based on polytetrafluoroethylene with the required operational properties include a preliminary separate preparation of the matrix and the fillers before their mixing by means of mechanical activation under different modes of equipment, as a result of which an increase in the indices of strength at break and wear resistance occurs.A synergistic effect of using mechanical activation of both matrix polytetrafluoroethylene and the fillers before their mixing was displayed by an increase in the indices of performance characteristics of the obtained composites: with a fibrous filler, strength at break increased by 18,6 %, relative elongation – by 28 %, wear resistance – by 6,9 times; with a dispersed filler, strength at break increased by 19,3 %, relative elongation – 27,6 %, wear resistance – by 1,7 times in comparison to the use of non-activated ingredients.The technology we developed for obtaining antifriction polytetrafluoroethylene composite of a new generation made it possible to increase wear resistance of materials by 3,7–6,0 times, strength at break – by 1,4 times compared to materials of the old generation.The rings of the compressor 4GM 2,5 U-3,4/2,8-251, made of the designed composite, allowed us to increase working resource of equipment of compressor engineering by 1,8–2,3 times.Исследовано влияние механохимической активации матрицы, наполнителей различной природы и композиции на структуру и эксплуатационные свойства политетрафторэтиленовых композитов. Установлены оптимальные режимы процесса механической активации матричного политетрафторэтилена, волокнистых и дисперсных наполнителей. Показано, что разработанные композиты на основе политетрафторэтилена с активированными ингредиентами по уровню прочности, износостойкости и долговечности существенно превышают аналогиДосліджено вплив механохімічної активації матриці, наповнювачів різної природи і композиції на структуру та експлуатаційні властивості політетрафторетиленових композитів. Встановлено оптимальні режими процесу механічної активації матричного політетрафторетилену, волокнистих і дисперсних наповнювачів. Показано, що розроблені композити на основі політетрафторетилену з активованими інгредієнтами за рівнем міцності, зносостійкості і довговічності істотно перевищують аналог

Modeling of Polymer Composite Materials Chaotically Reinforced with Spherical and Cylindrical Inclusions

The technical and economic efficiency of new PCMs depends on the ability to predict their performance. The problem of predicting the properties of PCMs can be solved by computer simulation by the finite element method. In this work, an experimental determination of the physical and mechanical properties of PTFE PCMs depending on the concentration of fibrous and dispersed filler was carried out. A finite element model in ANSYS APDL was built to simulate the strength and load-bearing capacity of the material with the analysis of damage accumulation. Verification of the developed computer model to predict the mechanical properties of composite materials was performed by comparing the results obtained during field and model experiments. It was found that the finite element model predicts the strength of chaotically reinforced spherical inclusions of composite materials. This is due to the smoothness of the filler surfaces and the lack of filler dissection in the model. Instead, the prediction of the strength of a finite element model of chaotically reinforced cylindrical inclusions of composite materials requires additional analysis. The matrix and the fibrous filler obviously have stress concentrators and are both subject to the difficulties of creating a reliable structural model

Using Regression Analysis for Automated Material Selection in Smart Manufacturing

In intelligent manufacturing, the phase content and physical and mechanical properties of construction materials can vary due to different suppliers of blanks manufacturers. Therefore, evaluating the composition and properties for implementing a decision-making approach in material selection using up-to-date software is a topical problem in smart manufacturing. Therefore, the article aims to develop a comprehensive automated material selection approach. The proposed method is based on the comprehensive use of normalization and probability approaches and the linear regression procedure formulated in a matrix form. As a result of the study, analytical dependencies for automated material selection were developed. Based on the hypotheses about the impact of the phase composition on physical and mechanical properties, the proposed approach was proven qualitatively and quantitively for carbon steels from AISI 1010 to AISI 1060. The achieved results allowed evaluating the phase composition and physical properties for an arbitrary material from a particular group by its mechanical properties. Overall, an automated material selection approach based on decision-making criteria is helpful for mechanical engineering, smart manufacturing, and industrial engineering purposes

Using Regression Analysis for Automated Material Selection in Smart Manufacturing

In intelligent manufacturing, the phase content and physical and mechanical properties of construction materials can vary due to different suppliers of blanks manufacturers. Therefore, evaluating the composition and properties for implementing a decision-making approach in material selection using up-to-date software is a topical problem in smart manufacturing. Therefore, the article aims to develop a comprehensive automated material selection approach. The proposed method is based on the comprehensive use of normalization and probability approaches and the linear regression procedure formulated in a matrix form. As a result of the study, analytical dependencies for automated material selection were developed. Based on the hypotheses about the impact of the phase composition on physical and mechanical properties, the proposed approach was proven qualitatively and quantitively for carbon steels from AISI 1010 to AISI 1060. The achieved results allowed evaluating the phase composition and physical properties for an arbitrary material from a particular group by its mechanical properties. Overall, an automated material selection approach based on decision-making criteria is helpful for mechanical engineering, smart manufacturing, and industrial engineering purposes.</jats:p

Impact of Nitrocarburizing on Hardening of Reciprocating Compressor’s Valves

One of the urgent problems in reciprocating machinery is ensuring the functional properties of direct-flow valves. Coatings of these parts should increase energy efficiency, reduce compressed gas temperature, and increase compressor performance. In this article, the effect of nitrocarburizing in pastes on increasing the performance and resource of such valves was studied. The primary research methods were metallographic and electron-metallographic research of the surface layer structure of steel 60Si2Cr. Comparison with similar characteristics obtained for stainless steel 09Cr15Ni8Al was also performed. As a result, it was determined that nitrocarburizing of carbon spring steel 60Si2Cr leads to a greater depth of the diffusion layer than nitrocarburizing of alloyed chromium-nickel steel 09Cr15Ni8Al. Simultaneously, the diffusion layers of both types of steel are almost the same. Simultaneously, the increase in the endurance limit of 60Si2Cr steel during nitrocarburizing is about 1.3 times compared to untreated material. Finally, the predictive maintenance showed that the evaluated lifetime of nitrocarburized valves increases by 5.7 times compared with untreated valves.</jats:p

Using Regression Analysis for Automated Material Selection in Smart Manufacturing

In intelligent manufacturing, the phase content and physical and mechanical properties of construction materials can vary due to different suppliers of blanks manufacturers. Therefore, evaluating the composition and properties for implementing a decision-making approach in material selection using up-to-date software is a topical problem in smart manufacturing. Therefore, the article aims to develop a comprehensive automated material selection approach. The proposed method is based on the comprehensive use of normalization and probability approaches and the linear regression procedure formulated in a matrix form. As a result of the study, analytical dependencies for automated material selection were developed. Based on the hypotheses about the impact of the phase composition on physical and mechanical properties, the proposed approach was proven qualitatively and quantitively for carbon steels from AISI 1010 to AISI 1060. The achieved results allowed evaluating the phase composition and physical properties for an arbitrary material from a particular group by its mechanical properties. Overall, an automated material selection approach based on decision-making criteria is helpful for mechanical engineering, smart manufacturing, and industrial engineering purposes

Modeling and Optimization of Properties of the Environmentally Clean Molds Based on Oligofurfuryloxysiloxanes for the Production the Metal Castings

This article is devoted to modeling, researching and optimizing the main properties of an environmentally clean polymer composition based on oligofurfuryloxysiloxanes (OFOS), which can be used to produce casting molds and cores in the production of castings from ferrous and nonferrous metals. Polymer compositions were examined for strength, survivability, gas permeability, moisture, crumbliness, fire resistance, knockout, and stickability. It has been established that the increase in the strength of the polymer composition over time obeys an exponential law. Mathematical equations were derived for all the exponential curves. The indications of compressive strength of the polymer composition with OFOS with all the acid catalysts used were, on average, as follows: after 1 h&mdash;1.3&ndash;1.54 MPa; after 3 h&mdash;2.5&ndash;2.9 MPa; after 24 h&mdash;4.9&ndash;6.1 MPa, which meets the requirements for casting molds before pouring with metal. The use of polymer compositions with OFOS ensures environmental safety of the technological process, due to the lack of emission of toxic substances, both in the &ldquo;cold&rdquo; stage of the process and during casting with molten metal, cooling, knocking out, and disposal of polymer compositions. This makes it possible to save energy resources, and thereby reduce the total cost of the entire technological process and castings

Increasing of physicochemical and performance properties of tribological PTFE composites by methods of mechanical activation

Досліджено вплив механічної активації політетрафторетиленової матриці на зміну структури, фізико-хімічних та експлуатаційних властивостей полімер-ного композиту.Исследовано влияние механической активации политетрафторетиленовои матрицы изменение структуры, физико-химических и эксплуатационных свойств полимерного композита.Shown the influence of mechanical activation polytetrafluoroethylene matrix of polymer composite on the structure and properties. Determined that the mechanochemical activation of polytetrafluoroethylene matrix affects on its su-pramolecular structure and performance characteristics. Chosen efficient grinding equipment and substantiated its operating modes. Shown the essential increase in performance properties of the activated polymer

Increasing of physicochemical and performance properties of tribological PTFE composites by methods of mechanical activation

Досліджено вплив механічної активації політетрафторетиленової матриці на зміну структури, фізико-хімічних та експлуатаційних властивостей полімер-ного композиту.Исследовано влияние механической активации политетрафторетиленовои матрицы изменение структуры, физико-химических и эксплуатационных свойств полимерного композита.Shown the influence of mechanical activation polytetrafluoroethylene matrix of polymer composite on the structure and properties. Determined that the mechanochemical activation of polytetrafluoroethylene matrix affects on its su-pramolecular structure and performance characteristics. Chosen efficient grinding equipment and substantiated its operating modes. Shown the essential increase in performance properties of the activated polymer