The tribological properties of complex polymeric materials, which include epoxy and polyester resins, two hardeners and two microdispersed fillers: mica-muscovite, copper (II) oxide, were investigated in the work. The results of the testing of specimens at dry friction and in the lubricant were analyzed. It is proved, that the antifriction properties of the composite depend on its composition, formation technology and testing conditions. It has been experimentally determined, that the material which was tested in the lubricating environment -I m = 0.25-0.30 mg/km, f = 0.03-0.04, differs with the improved indexes of wear rate and friction coefficient. As a result of the analysis of investigated microsurfaces studied by optical and electron microscopy, the phase heterogeneity of the composite material system was identified. It contributes to the reduction of the running-in distance of the specimen, and indicates the uniform distribution of the filler particles on the surface, has been found. The elemental composition of the compound was determined, which indicates the direct involvement of fillers in the process of friction. A change in the ratio of atoms on the specimen surface before and after the test was found. The results of the study of the surface in the phase contrast mode correlate with the results of the data obtained by electron microscopy.
It is proved that in order to increase the operational characteristics of parts of the river and sea transport, including their physical and mechanical properties, it is advisable to use the protective polymeric composite coatings. The effect of fillers on the flexural stresses of the developed epoxy composite was analyzed. The critical content of components was determined by the method of mathematical planning of the experiment: the synthesized powder mixture - 0.05 pts.wt., discrete fibers - 0.10 to 0.15 pts.wt. per 100 pts.wt. of epoxy oligomer ED-20. Introduction of such ingredients into the epoxy binder allows to increase the flexural stresses to σ f=77.4…78.6 MPa. The obtained results allow to create materials with improved values of physical and mechanical properties.
The world wide pandemic situation revealed the problems in all spheres of human life which haven’t been faced before. Recently the world has changed greatly as well as the relationship between people and their professional activity. The great bunch of the workload, if basically acceptable, is done with the use of modern innovative technologies. Such problems have not trampled down the sphere of higher education as well. Distance learning, which was previously addressed to only as accompanying possibility of lessons conduct, nowadays is considered to be the only practicable form of conducting lectures, practical lessons, tests, i.e. it has become a usual daily practice for both teachers and students. Among the basic functional requirements to the electronic educational resources in the system of distance learning there are the visualization and interaction principles both when getting familiar with the theoretical material and when completing virtual laboratory and practical tasks. The Microsoft Office documents have become the most widespread elements among the electronic educational resources. That is why there is a pressing need in presenting the electronic MS Excel spreadsheets on the resource web-pages. The simple and convenient way to solve the problem of Excel documents introduction into the electronic resources of the distance learning systems is the use of cloud services. The services help to acquire the access to the information resources of any level and of any capacity with the possibility to allocate the rights of the users belonging to different groups in relation to the resources. For that purpose the availability of the Internet network access and web-browser would be enough \cite{Kravtsova2020}. The cloud calculation technologies introduction allows for the use of the programs that do not require special licensing, update versions monitoring and eliminates the need of software technical support as the provider himself exercises control over the functioning, data saving, antivirus protection and possible cyberassaults.The peculiarities of professional training of navigators require the students to acquire the knowledge of professionally-oriented tasks algorithms as well as the knowledge of technologies that can help to implements them. One of the main routines the officer needs to deal with on the navigational bridge is the use of the information systems of shipboard hardware. But before usage he needs to assure of the systems reliability. That is why it is extremely important to gain during the course of professional training the necessary skills of navigation equipment exploitation reliability assessment by means of Microsoft Office documents and cloud services. So the subject matter of the suggested research is the procedure development for the navigation equipment exploitation reliability assessment by means of modern services use in the course of professional training of future seafarers. The aim of the paper is the solution of the problems of optimum assessment of the information systems of shipboard hardware reliability by means of cloud technologies usage. The following tasks are completed in the course of the research: the peculiarities and characteristics of navigational information processed by the shipboard navigation and information system have been analyzed; the results of the information systems of shipboard hardware usage have been studied; the technological diagram of the basic components structuring of the “Information systems of shipboard hardware” complex for the Master’s degree training course has been created; the effective technology of the program Excel documents processing has been chosen; the system of access and usage of web-services for calculation tables processing in the system of distance learning has been designed;the process of competency formation which will enable students to use cloud services has been suggested.
Epoxy diane oligomer ED-20, 2,4-diaminoazobenzene-4'-carboxylic acid modifier, polyethylene polyamine hardener,microdispersed particles of synthesized powder charge and a mixture of discrete fibers were used to form composite materials and protective coatings for the transport industry. The influence of aggressive media: oil, gasoline, sea water, acetone, NaOH (50 %), HCl (10 %) and H2SO4 (10 %) on the corrosion resistance of the developed composite materials with different content of ingredients was studied. The results of experimental studies suggest that the least swelling was observed for samples of composite containing components in the following ratio – modified binder: microdisperse filler in the form of a synthesized powder charge (Fe (70 %) + Ti (10 %) + TiC ) + Fe3C (5 %)) (d = 10–12 mm) : mixture of discrete fibers (modal (42 %), polyacrylic (38 %), polyamide (38 %)) – 100 : 0.05 : 0.10. The use of such a composite in the form of protective coatings of vehicles will ensure (if compared to the modified epoxy matrix) reduction of the permeability of aggressive media in: 1.5–1.7 times (when being used in oil and gasoline); 1.6–1.8 times (when being used in seawater, acetone and NaOH solution (50 %)); 3.0 and 2.5 times (when being used in solutions (10 %) of hydrochloric and sulfuric acids, respectively. Increased corrosion resistance compared to the matrix is caused by a decrease of the amount of polymer in the developed material and its increased cohesion strength, which increases the path of penetration of molecules of corrosive agents during their diffusion into the composite due to additives.
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