Epoxy-diane oligomer ED-20, hardener polyethylene polyamine, and micro dispersed particles of iron-carbide mixture synthesized by high-voltage electric discharge have been used for the formation of Composite Materials (CMs) and protective coatings for the transport industry. The dependence of the adhesive, physical, and mechanical properties and residual stresses of epoxy composites on the content of micro dispersed powders has been studied in this paper. It has been proved that for the formation of a composite material or protective coating with improved adhesion and cohesion properties, the optimal content of particles is 0.5 wt.% per 100 wt.% of epoxy oligomer ED-20. Such materials are characterized by increased mechanical strength and the ability to resist static and shock loads, as their properties are significantly increased. The obtained results of the experimental studies of the physical and mechanical properties of composite materials correlate with the studied results of adhesive characteristics, which indicate their veracity.
Taking into account current trends in the development of ergatic maritime transport systems, the factors of the navigator’s influence on vessel control processes were determined. Within the framework of the research hypothesis, to improve navigation safety, it is necessary to apply predictive data mining models and automated vessel control. The paper proposes a diagram of the ergatic vessel control system and a model for identifying the influence of the navigator “human factor” during navigation. Within the framework of the model based on the principles of navigator decision trees, prediction by data mining means is applied, taking into account the identifiers of the occurrence of a critical situation. Based on the prediction results, a method for optimal vessel control in critical situations was developed, which is triggered at the nodes of the navigator decision tree, which reduces the likelihood of a critical impact on vessel control. The proposed approaches were tested in the research laboratory “Development of decision support systems, ergatic and automated vessel control systems”. The use of the Navi Trainer 5,000 navigation simulator (Wärtsilä Corporation, Finland) and simulation of the navigation safety control system for critical situations have confirmed its effectiveness. As a result of testing, it was determined that the activation of the system allowed reducing the likelihood of critical situations by 18–54 %. In 11 % of cases, the system switched the vessel control processes to automatic mode and, as a result, reduced the risk of emergencies. The use of automated data mining tools made it possible to neutralize the negative influence of the “human factor” of the navigator and to reduce the average maneuvering time during vessel navigation to 23 %
The tribological properties of epoxy-composite materials filled with nano-and microdispersed particles and thermoplastic under the influence of the environment of seawater have been analyzed. It has been found that the composition of the material, friction conditions and the marine environment significantly affect the tribological properties of composites. The tribological properties of the developed epoxy matrix, which contains two different hardeners, have been studied. Improvement of the tribological properties of composites with the introduction of nanographite and pearlite particles into their composition has been proved. A method for improving the antifriction properties of polymer composite materials by combining a thermoset matrix filled with nano-and dispersed particles with thermoplastic granules has been proposed. It is proved that the tribological properties of epoxy-composite thermosetting plastics have been improved by adding granules of a thermoplastic filler called PA-6 polyamide into their composition during friction under the influence of seawater. On the basis of the obtained research results, the assumptions of the mechanism of wear of epoxy composites with a two-component bidispersed filler have been suggested. To confirm the results obtained, the study of the surface roughness of the composites in the contact area after friction testing using a profilometer, as well as an optical method, has been conducted. Recommendations are given for the use of the developed composite with thermoplastic granules for the manufacture of sliding bearings.
In the article the polymeric materials based on epoxy-polyester binder with addition of dispersed fibers were developed. The mechanical and thermophysical methods were used. The influence of carbon fibers (0.01–0.30 pts.wt.) and cotton (0.01–0.30 pts.wt.) on the physical and mechanical, thermophysical properties of epoxy-polyester composites was investigated. The results of the experiment showed that the introduction of carbon fibers leads to an increase in the fracture stresses, the flexural modulus; the maximum increase was observed for the carbon fiber content q = 0.01 pts.wt. (fl = 71.0 MPa, E = 3.8 GPa, W = 7.8 kJ/m2 ). The heat resistance of composite materials at this content of carbon fibers is maximal (T = 337 K), and the coefficient of linear thermal expansion (CLTE) is minimal and decreases in all temperature ranges (compared to the matrix). It was found, that the introduction of cotton fibers at a content q = 0.02 pts.wt. into the composition leads to an increase of the flexural modulus from E = 3.6 GPa (matrix) to E = 3.8 GPa and flexural stresses from fl = 50.4 MPa to fl = 55.2 MPa. The impact strength of such materials decreases from W = 8.3 kJ/m2 to W = 4.9 kJ/m2 . The results of the study of physical and mechanical properties of composite materials with the addition of cotton fibers were confirmed by thermophysical properties. It was found, that the heat resistance of materials increases from T = 335 K to T = 338 K at this content. The developed composite materials filled can be used to protect equipment, which are exposed to high temperatures or dynamic loads at moderate temperatures.
The prospective of the application of new materials on a polymer base is shown in this work. Given that developed composites can be efficiently used for protection of equipment that is operated at elevated temperatures, the impact of the nature and content of powder mixture, synthesised by high voltage electric discharge, on the thermophysical properties of epoxy composites were studied. Epoxy diane oligomer was chosen as the main component of the binder during the formation of the composites. Polyethylene polyamine hardener was used for cross-linking of epoxy composites, which allows hardening of materials at room temperatures. The selection of powder mixture, synthesised by high voltage electric discharge, for increase of thermophysical properties of developed materials was justified. More so, thermal stability and activation energy of epoxy composites were studied. Permissible limits of the temperature, at which developed materials can be used, were established based on the conducted tests of thermophysical properties of materials, filled by powder mixture, synthesised by high voltage electric discharge.
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