The paper presents investigation results pertaining to  ascertainment of formation regularities of phase composition and structure during mechanical alloying of binary aluminium composites/substances. The invetigations have been executed while applying a wide range of methods, devices and equipment used in modern material science. The obtained data complement each other. It has been established that presence of oxide and hydro-oxide films on aluminium powder  and introduction of surface-active substance in the composite have significant effect on mechanically and thermally activated phase transformations and properties of semi-finished products.  Higher fatty acids have been used as a surface active substance.

The mechanism of mechanically activated solid solution formation has been identified. Its essence is  a formation of  specific quasi-solutions at the initial stage of processing. Mechanical and chemical interaction between components during formation of other phases has taken place along with dissolution  in aluminium while processing powder composites. Granule basis is formed according to the dynamic recrystallization mechanism and possess submicrocrystal structural type with the granule dimension basis less than 100 nm and the grains are divided in block size of not more than 20 nm with oxide inclusions of 10–20 nm size.

All the compounds  with the addition of  surface-active substances including aluminium powder without alloying elements obtained by processing in mechanic reactor are disperse hardened. In some cases disperse hardening is accompanied by dispersive and solid solution hardnening process. Complex hardening predetermines a high temperature of recrystallization in mechanically alloyed compounds,  its value exceeds 400 °C.

Alloy solidification at high cooling rates leads to significant changes in structure and phase composition. Conditions appear for a significant extension of solid solubility, grain refining, and formation of metastable phases or amorphous state. Due to this it is possible to obtain  unique combinations of physical, mechanical and other properties in rapidly quenched alloys. Undoubted scientific and practical interest is an application of  quenching processes from a liquid state for aluminum alloys with the purpose to improve their physical and mechanical properties.

As the structure of such alloys is extremely unstable from a thermodynamic point of view the important issue is to study  temporal stability of the microstructure and phase composition of rapidly quenched aluminium alloys of various chemical composition. The paper has investigated an influence of various alloying elements on the structure, phase composition and durometric properties of aluminum foils obtained by liquid aluminum alloy melt-spinning on the disk rotating with various speed. Optical and electron microscopy  has been used to study structure and phase composition as well as X-ray structural analysis. It has been shown that alloying of aluminium with copper leads to an increase in micro-hardness up to 130–160 HV0.01, and alloying with chromium and zirconium provides micro-hardness up to 60–80 HV0.01. It has been shown that increasing in amount of alloying additions in the aluminum melt (Al–Cu system alloy) rises the number of CuAl₂ precipitates and is accompanied with an increase in micro-hardness of aluminum foils. An increase in cooling rate of the aluminum melt (Al–Cr–Zr system) is accompanied with structure dispersion which increases micro-hardness of the casted foils. The obtained results have made it possible to establish the optimal percentage of alloying elements and the disk rotation speed providing the highest level of aluminium foils’ durometric properties.

The modern development of industrial production is closely connected with the use of science-based and high technologies to ensure competitiveness of the manufactured products on the world market. There is also much tension around an energy- and resource saving problem which can be solved while introducing new technological processes and  creation of new materials that provide productivity increase through automation and improvement of tool life. Development and implementation of such technologies are rather often considered as time-consuming processes  which are connected with complex calculations and experimental investigations. Implementation of a simulation modelling for materials processing using modern software products serves an alternative to experimental and theoretical methods of research.

The aim of this paper is to compare experimental results while obtaining bimetallic samples of a forming tool through the method of speed hot extrusion and the results obtained with the help of computer simulation using DEFORM-3D package and a finite element method. Comparative analysis of plastic flow of real and model samples has shown that the obtained models provide high-quality and reliable picture of plastic flow during high-speed hot extrusion. Modeling in DEFORM-3D make it possible to eliminate complex calculations and significantly reduce a number of experimental studies while developing new technological processes.

The purpose of the paper is to modernize technology for obtaining high-accuracy lenses with fine centre. Presently their operating surfaces are fixed  to an accessory with the help of adhesive substance that leads to elastic deformation in glass and causes local errors in lens parts.

A mathematical model for concurrent two-sided processing of high-accuracy optical parts with spherical surfaces has been developed in the paper. The paper presents analytical expressions that permit to calculate sliding speed at any point on the processed spherical surface depending on type and value of technological equipment settings. Calculation of parameter Q = Pv in a diametric section of the convexo-concave lens has been carried out while using these expressions together with functional dependence of pressure on contact zone еarea of tool and part bedding surfaces.

Theoretical and experimental investigations have been carried out with the purpose to study changes in Q parameter according to the processed lens surface for various setting parameters of the technological equipment and their optimum values ensuring preferential stock removal in the central or boundary part zone or uniform distribution of the removal along the whole processed surface have been determined in the paper.

The paper proposes a machine tool scheme for concurrent two-sided grinding and polishing of lenses while fixing their side (cylindrical) surface. Machine tool kinematics makes it possible flexibly and within wide limits to change its setting parameters  that significantly facilitates the control of form-building process of parts with highly-precise spherical surfaces.

Methodology for investigations presupposes the following: mathematical simulation of highly-precise spherical surface form-building process under conditions of forced closing, execution of numerical and experimental studies.  

The paper presents optimization of  processes for obtaining maximum content of tetragonal phase in the initial material and thermal barrier coatings (TBC) based on zirconium dioxide and hafnium oxide.  Results of the investigations on phase composition of oxide HfO₂ – ZrO₂ – Y₂O₃  system have been given in the paper. The system represents  a microstructure which is similar to  zirconia dioxide and  transformed for its application at 1300 °C. The paper explains a mechanism of hafnium oxide influence on formation of the given microstructure. The research methodology has been based on complex metallography, X – ray diffraction and electron microscopic investigations of  structural elements of the composite plasma coating HfO₂ – ZrO₂ – Y₂O system.

In order to stabilize zirconium dioxide  dopant oxide should not only have an appropriate size of  metal ion, but also form a solid solution with the zirconia. This condition severely limits the number of possible stabilizers. In fact, such stabilization is possible only with the help of rare earth oxides (Y₂O₃, Yb₂O₃, CeO₂, HfO₂). Chemical purity of the applied materials plays a significant role for obtaining high-quality thermal barrier coatings. Hafnium oxide has been selected as powder for thermal barrier coatings instead of zirconium dioxide due to their similarities in structural modification, grating, chemical and physical properties and its high temperature structural transformations. It has been established that plasma thermal barrier HfO₂ – ZrO₂ – Y₂O₃ coatings consist of  one tetragonal phase. This phase is equivalent to a non-equilibrium tetragonal t' phase in the “zirconium dioxide stabilized with yttrium oxide” system. Affinity of  Hf⁺⁴ and Zr⁺⁴ cations leads to the formation of identical metastable phases during rapid quenching.

population of the Republic. Quality of the road traffic or its specific characteristics can be quantitatively estimated  in terms of losses and by that we understand social and economic value of non-obligatory expenses in road traffic. That is why any decision on road traffic organization must be estimated and optimized in accordance with its loss minimization criterion (accidental, economic and ecological).

Research and Development Centre for Road Traffic at the BNTU Branch - “Research Division” has developed loss methodology in road traffic for  conflict objects – roads crossings and speed cushions. Such approach has made it possible to compare two alternative options for organization of road traffic at conflict objects. The paper considers an example of selection and substantiation of the accepted decision for an uncontrolled  T-junction with closely located pedestrian crossing in the Ya. Kolas Street, Building 12, Minsk. Planning and organizational and technical measures that increase road traffic safety and decrease economic and ecological losses have been developed on the basis of the executed investigations. The investigations and analysis of the existing conditions of the road traffic at the uncontrolled Ya.Kolas Street –Ya.Kolas off-street junction have revealed that the rate of total losses in the road traffic constitutes   nearly 92,000 c.u./year, including accidental losses – 7,900 c.u./year. Realization of the developed measures will permit to reduce the rate of accidental losses at pedestrian crossing approximately by 4,400 c.u./year with reduction of accidents by 50–55 %

The paper presents a mathematical model for electronic control system of the angular ignition timing (AIT) in the (ICE), which is running on ozonized fuel. An algorithm for  ignition system control of internal combustion engine using ozonized fuel has been developed in the paper. A structure of the dynamic ignition system while using a control unit for supplying  ozone into fuel with a purpose to improve automobile ecological and economical indices adapted to operational conditions. Application of the given system allows to ensure minimum reduction of operational petrol consumption and concentration of incomplete combustion products due to optimum ozone dosage into the fuel.  The paper proposes a controlled automobile ignition system as a sequential scheme which has a great number of discrete inputs and outputs and many discrete internal  states. The scheme establishes a functional dependence between input and output states. The paper provides an assessment of ecological indices according to massive emissions of carbon monoxide СО, hydrocarbon С_пН_т and nitric oxide NO_x .  The analysis of  investigations results has been carried out in the paper.

Elastic modulus accuracy using atomic force microscopy  depends significantly on processing quality of the experimental data obtained during nanoindentation.  Multiply repeated calibration can lead to conservative value of the calibration factor.  Such artefact is caused by probe slipping on silicon plate surface which is harder than  surface of the investigated specimen and which is non-uniform  in height. Elastic modulus calculated by the Hertz model depends on penetration value  while processing the indentation data at small depth of the probe penetration into the specimen.  A value  being close to asymptotical one  which is obtained  at rather large object deformation is taken as a required modulus. Such deformation is not always possible in an experiment,  or  it is achieved with rather large (tens of percent) relative deformations that is beyond permissible region of the Hertz model application.

The purpose of this paper is to demonstrate several new opportunities for  nanoindentation data processing, as at the stage of obtaining or verifying a calibration factor of the atomic force microscope so while analyzing an investigated object penetration curve.  The paper considers two methodologies for determination of the calibration factor on the basis of the Hertz  and Johnson-Kendall-Roberts models and proposes new mechanisms for determination of  elastic modulus while using method of atomic force microscopy.  The possibility to calibrate atomic force microscope according to material with known mechanical properties has been shown in the paper. The paper substantiates the necessity and provides an algorithm  for correction of the measured probe penetration depth with due account of  adhesive forces while calculating the in the region of small specimen deformations. The proposed methods for determination of the calibration factor and  asymptotic value of the elastic modulus will be useful for obtaining  reproducible and more accurate results of atomic force microscopy for mechanical properties.

The paper presents a new method for obtaining pulp which is used for production of cardboard, paper and package while using carbon dioxide and hydrazine hydrate and neutral-sulfite  shive cooking. Output increase of  the desired product can be explained by reduction in destruction of plant raw material carbohydrates during its cooking process. Quality improvement of the desired product (improvement in bleaching and output) is attributed to the fact that usage of carbon dioxide and hydrazine contributes to provision of polysaccharide chain resistance to destruction due to the presence of  end links having structure of metasaccharinic and aldonic acids.

The author has developed a new method for pulp obtaining on the basis of the executed investigations  and literature data.  СО₂ and hydrazine hydrate have been used for obtaining pulp. Method invention concerns pulp obtaining and it can be used for paper and cardboard package manufacturing in pulp and paper industry.

The method is to be carried in the following way: pulp-containing plant raw material is loaded into an autoclave and then aqua solution of sodium monosulfite containing hydrazine hydrate that constitutes 4–5 % of absolute dry pulp-containing raw material mass with liquid module 1:6–1:8 is supplied into the autoclave. The autoclave is closed for operation under pressure and the solution is carbonated under pressure which constitutes 5–8 % of absolute dry plant raw material (shover). Temperature is subsequently raised up to 180 °С in the space of 2 hours and cooking is carried out in the course of 4 hours. Usage of  the proposed method for shover cooking makes it possible to reduce monosulfite cooking process and improve qualitative characteristics and output of the desired product.  In addition to above mentioned fact there is a possibility to improve bleaching and final product output. 

The paper presents  a calculation of contact tensions between conjugate surfaces in sphere globoidal rusk synchronous cardan hinge on the condition that there is power balance at the constant torque on the output shaft. The required torque effect on the intake shaft at the constant angular velocity  has been calculated with the help of the Hertz’s theory of contact deformations . The maximum contact pressure has been ascertained through the torque which determines strength of the cardan hinge, its durability, wear rate in  the conjugate friction pair. The paper investigates transmission dependence of the maximum torque while changing  material quality and according to various typical sizes of the cardan hinge. Dependences of the calculated maximum torque value on material strength have been demonstrated graphically  in the logarithmic coordinate system.  A formula for maximum contact pressure value has been derived and it determines  strength of the hinge mechanism, its durability and wear rate  in the conjugate friction pair.

The effect of geometrical relationship between a spherical cam radius and a globoidal  surface radius of a hinge contact has been determined with the purpose to analyze optimal design parameters of the sphere globoidal rusk synchronous cardan hinge. It has been established that permissible torque in the hinge mechanism grows with a quadratic dependence while increasing a cam radius and  the torque is proportionally growing while increasing an axis radius of globoidal rusk surface on which spherical cams are set. The maximum permissible torque value grows with a cubic dependence while using qualitative material with thermally treated surface and application of lubrication materials which tolerates significant (up to [σ] = 1000 MPa) contact loads.  Two-fold increase of typical size of the sphere globoidal rusk synchronous cardan hinge leads to an 8-fold increase of the permissible transmitted torque.

The paper considers an important problem in improvement of  braking dynamics potential as part of the overall tractor train dynamics consisting of  an all-wheel drive tractor and heavy-duty trailers which are either locally manufactured or developed with the participation of the paper’s authors. The trailers have a mechanical drive for their wheels from the tractor engine. The trains are intended for transportation peat, organic fertilizers and various loads in  forest exploitation and under other complicated soil and climatic and road conditions where there is justified necessity to activate the trailer wheels.

Methodological tools have been developed with the purpose to analyze an influence of the blocked inter-double-reduction axle drive of an active tractor train on distribution of braking forces in double-reduction axles with due account of the heavy-duty peat trailer specificity. Theoretical provisions for wheeled vehicles have been developed with regard to the braking application specificity of active tractor trains with mechanical multi-path drive for wheels of a multi-double-reduction axle propulsion device. The paper presents calculation and theoretical data in order to estimate  distribution of specific braking forces in the double-reduction axle links of the active tractor train when the blocked inter-double-reduction axle drive of the tractor and trailer wheels is switched on and also in the case when the tractor engine is involved in braking process and a clutch coupling is switched-on.

Sequence of the calculation formula has been completely carried out in the paper. They represent clear design and operational parameters of the active tractor train. Such approach has made it possible to realize them in the form of a software application which is convenient for analysis of the braking process pertaining to the investigated objects in order to select means for improvement of braking dynamics, rational parameters of multi-path wheel drive and tire completing of the active tractor train under design. The proposed information has a theoretical and practical value for specialists who are involved in development of new machine-tractor units for transport application in peat extraction, forestry, and agriculture.

The paper considers problems on regulation of phase composition of a nitrided layer during gas and ion nitriding process in a glow-discharge. It has been established that  available models for control of nitrided layer structure with the help of nitriding index (nitrogen potential) can not be applied for nitriding process in the glow-discharge. Principal difference of the ion nitriding from the gas one is in the fact that chemically active nitrogen is formed in the discharge zone (cathode layer) and its mass-transfer is carried out in the form of an active particle flow (ions, atoms, molecules) which directed to the metal surface.

Interrelation of chemical discharge activity with such characteristics of nitriding steel as nitrogen solubility in  α-solid solution and  coefficient diffusion during ion nitriding in low-discharge plasma. It has been shown that regulation of the nitride layer structure during ion nitriding is reached due to changes in nitrogen flow density in plasma. While supporting the flow at the level of nitrogen solubility in  one phase or another (α, γ′)  it is possible to obtain the nitrided layer consisting only of α-solid solution or γ′-nitride layer and diffusion sub-layer. Moreover a specific range of nitrogen flow density values exists for every steel grade where it is possible to ensure a limiting nitrogen concentration in α-solid solution and the γ′-layer characterized by low diffusion  mobility is not formed on the surface.