This study contains main views and scientific principles of its authors, used as a basis for mathematical modeling, oriented to the synthesis of kinematically conjugated spatial (hyperboloid) gear drives.
Machines. Technologies. Materials.
Vol. 12 (2018), Issue 6
Table of Contents
The evaluation of the quality of production process on mechanical properties of reinforcing bars profile 10-32 of steel grade 35GS was performed, obtained in the conditions of the rolling production of JSC “ArcelorMittal Temirtau”. Using a complex quality parameter, the process of rebar production is characterized as stable and controlled.
A novel technology for producing metal powders is presented, the distinctive feature of which are the conditions of forming of powder particles. In particular, under the proposed technology the melt is sucked bottom-up by the vacuum produced by the toroidal vortex of the discharged nucleus of high-pressure water flow in the two-layer cylindrical shell cavity, where it is being dispersed as metallic particles and carried over from the working medium to a special store. The so produced powders have a particular morphology and structure, increased specific surface area and microhardness.
The peculiarities of evaluation of stress-strain state of the pressure hull of the underwater technical device, shaped as torus with circle intersection, which was obtained by transverse winding combined with longitudinal winding (or facing) of polymer materials, while taking variable thickness by meridian section into an account, are presented.
In this study, series of CFD simulation were carried out for two phase flow (free surface), three dimensional geometry and turbulent flow through the pelton turbine. The present investigation employed on the pelton turbine bucket models various splitter angle and inlet velocity values for visualizing the flow pattern and identifying the force on the bucket. In this study, Two different bucket models were applied at different inlet velocity (20, 25, 30,35and 40m/s) and four different splitter angle (55, 75,90and 115) for finding the effect of every single parameter on the effective force on the bucket. The obtained results discovered that there is a linear relationship between force and inlet velocity on the bucket. It uncovered that relationship between splitter angle and force on the bucket is linear until 90 degree after that this relationship is a non-linear.
The parallel functioning of strategies for innovative and sustainable development leads to the emergence of a formal methodological paradox in the form of increasing negative technological impact on the environment due to the prevalence of economic criteria for assessing the efficiency of production over social criteria. This paradox determines the permanent growth of products that can be combined with the concept of waste. To eliminate the methodological paradox, it is necessary to implement the ecological imperative by greening the legal framework that regulates all stages of the life cycle of innovative products.
An aim of a research was to determine the reasons of fracture of aluminium alloy components used for spinning of chemical fibres and to improve spinning process by selecting material with better performance.
The potential of using the ultrafine dispersion powder material obtained by the ECA pressing from a copper powder have considered for the production of fast-acting fuse links. The dependences of the density and microhardness along the length of the sample under different deformation conditions obtained. A deformation zone of constant density is determined and recommended for using in the production of fuse links. The dependence of the electrical resistance along the sample cross-section and across the deformation axis has determined. The fuse links calculation procedure has proposed.
The work considers the use of carbon nanotubes to enhance the functional characteristics of polymer materials. The results on studies of the electrophysical properties of polymers doped with carbon nanotubes are presented and prospects for the use of such materials are discussed.
The results of experimental studies of the compression process during the sintering under high pressure conditions of wurtzite boron nitride and diamond powders mixture of submicron sizes obtained by different technologies are given. It is determined that the compaction level at obtaining compositions depends on the dispersion and nature of the diamond component. Interaction of wurtzite boron nitride with diamond proceeds more intensively with diamonds of dynamic synthesis, but it is accompanied by their partial graphitization.
INVESTIGATION OF THE EFFECT OF PRODUCTION PARAMETERS ON POLYSTYRENE NANO FIBER FORMATION FOR 12 WT %, 14 WT % AND 16 WT %pg(s) 262-265
Polystyrene (PS) is a versatile plastic used to produce a wide variety of consumer products. It is used as a hard, solid plastic, mostly as food packaging and laboratory products. When polystyrene is mixed with various colorants, additives or other plastic materials, it is used to make electronic parts, automobile parts, toys, pots and equipments and more. Polystyrene is a vinyl polymer. It is structurally a long hydrocarbon chain with a phenyl group attached to the carbon atom. Polystyrene is produced by free radical vinyl polymerization from monomer styrene. In this study, the effect of production parameters on the formation of PS nanofibers was investigated. For this purpose, solutions were prepared at various mixing ratios (12 wt %, 14 wt % and 16 wt %) consisting of PS + dimethylformamide (DMF). The nanofiber structure was determined from these solutions. Electrospin method was used in production of nanofibers.