Papers by Keyword: Surface

Abstract: Abrasion measurement of surface of specific concrete elements is presented in this paper. This article is focus on determination of wear resistance and strength of concrete floor. This concrete contains silicon carbide binder and part of it is recycled origin. This material are high on Mohr hardness scale and are they are suitable for use in indoor and outdoor areas with the heaviest traffic loads. From the results, follows that the even small differences in mixture (using new and recycled binder) has impact on the mechanical parameters. However, it is possible design mixture with recycled binder and reach characteristic of concrete, which are almost similar to the normal concrete.

Abstract: Electron beam (EB) and heat treatment of silica-containing aggregates and mineral additives for Portland cement mortars is shown to affect their activity in alkali-silica reaction (ASR) damaging concrete structures. In the case of ordinary mortar based on the sand free of alkali-reactive inclusions, both heating to 900°C and EB processing result in a significant increase of reactivity growing with the absorbed dose in the range from 100 to 600 kGy and correlating with the increase in the content of acidic hydroxyl groups on the surface. For sand with reactive chalcedony inclusions, EB treatment results in the growth of their reactivity while heating provides its significant decrease. In case of mineral additives such as silica fume and metakaolin known as very effective ASR-inhibitors, similar processing leads to the increase of their activity in mitigation of ASR. The observed effect is promising for simulation of expansion processes caused by ASR and enhancement of concrete structure resistance to alkali destruction during exploration.

Abstract: The article presents the fractal approach to the study of the five peat structure samples. Digital images from natural porous raw peat, intended for fractal studies of the porosity, are proposed. Peat active porosity is used in this study. In this study, the peat active porosity, fractal dimension (D), and their relationship with different peat samples were investigated in an experiment. The results of this study demonstrate that a fractal dimension analysis of peat compositions texture is a useful method for the quantitative description of the active porosity. The received results should be considered in the theoretical and pilot studies connected with physicomechanical processes occurring on the porous surfaces of peat raw materials during its mechanical processing.

Abstract: Results of the design analysis carried out using computer software are presented for boundary data complying with the currently operating state-of-the-art arc steel furnace. Flow of natural gas combustion products and oxygen are reviewed for the radial and tangential burner arrangement in the working space between the wall and the electrodes. Location of high temperature fields is determined and the expected heat transfer to the charge materials through the active surface participating in heat exchange is evaluated. Precipitation degree is determined for the dust participating in scull generation on a wall water-cooled surface and significant reduction of dust effect on electrodes.

Abstract: In this paper, we research the relief of surfaces of wedge bodies of freewheeling mechanisms. The results obtained by scanning probe microscope let us correct predicted deterioration parameters of a wedge body and consider the effect of surfaces’ altitude quality indicators while designing mechanisms. Mark out relative area of bearing.

Abstract: The practice shows availability of an electro plasma method polishing. The lack of a method, namely impossibility of its application for processing extended grooves and apertures is known. Creation of a special equipment and revealing of optimum modes have allowed to receive the given roughness on the named surfaces on products from cuprum.

Abstract: Technological difficulties of manufacture, typical to the large number of crucial elements of certain assemblies: tubes of fuel systems, details of waveguide devices, smooth gun barrels and other tubular details. Difficulties associated with the finishing of the internal surfaces of these products. Therefore, great interest is to find a finishing technology, which allow processing such products. The kind of electrolytic-plasma polishing technology - forced electrolytic-plasma polishing (FEPP) allows to receive homogenous quality of an internal surface layer along processed tubular work piece.

Abstract: Proposed a method for measuring parameters of micro-surface machine parts optoelectronic and computer facilities, based on the computation of two-dimensional settings of the autocorrelation function, based on the binary image of the investigated microrelief using kvazioptimalnogo correlation algorithm. Found to be the most informative characterization of the studied surfaces, micro precision components reliably distinguished from each other with a given probability, is the average amplitude of the variable component of the autocorrelation function. Shows the results of determining the parameters of microrelief surface of runner blade GTM using quasi-optimal correlation algorithms.

Abstract: The paper presents the results of studies on the activation of the surface of carbon and glass fibers by thermal and chemical treatment with acids and mixtures of acids. Carbon and glass fibers with an activated surface are of practical interest for the production of polymer composite materials with high thermal, physical and mechanical characteristics.

Abstract: The process of manufacturing polymeric material products includes the entire processing system; from their properties and the technical level of the manufacturing device, through its control and regulation system, and the manufacturing tools. This article deals with the study of aluminium alloy materials used in the manufacture of moulds - with different coatings, in order to reduce the surface contamination of the cavity moulds. The reason for choosing this topic is to discover a way as to how to understand the contamination process. The method chosen for eliminating such contamination is then, dependent on the degree of knowledge regarding the state and cause of the problem in the production process under investigation.