To be Updated with new approved abstracts

Cylindrical grinding process requires a large amount of specific grinding energy and the energy is dissipated as heat in the work surface resulting in increasing the surface temperature and localized plastic deformation. An increase in temperature at grinding interaction zone causes deterioration of the surface integrity, leading to grinding burns, induction of tensile residual stress and geometrical inaccuracies, so it's become important to understand the factors which affect grinding temperature. This work focuses on theoretical evaluation of maximum surface temperature so that the onset of grinding burn can be identified. It is known that, direct measurement of grinding temperature has been always difficult during the experiment method as the work-wheel interaction zone is fairly hidden and flooded with the coolant. Therefore, the evaluation of temperature would help the in early detection of possibility of the grinding burn. Grinding zone temperature evaluation reveals that, when the calculated grinding temperature reaches beyond the optimum value 631oC, this results in grinding burn on the surface with a BNA value of the order of 100 mp for medium carbon steel.

Ductile iron is one of the youngest material with unique constructions features, preferred combination of foundry and mechanical properties. To achieve the necessary quality ductile iron was necessary to establish the methods of control of liquid metal. The most modern and most accurate method is thermal analysis. This is quantitative criterion which comprehensively evaluates the made iron. Thermal analysis has been used in foundries for many years. Development in the field of electronics has resulted in quicker digital tools and displays, mainly for the determination of carbon and silicon contents and carbon equivalent. The displayed results include the previously mentioned information along with other estimated values such as the risk of the presence of carbides or microshrinkage and nodularization protential. Thermal analysis equipment provides a more accurate interpretation of the information available in the curves by taking into account the first and second derivatives of the cooling curves. Our aim was to examine changes in the metallurgical process and batching on the mechanical properties and structure of metal in compliance with the liquidus temperature. From the cooling curves and their derivations were observed process crystallization, graphitization ability, addiction to shrinkages and result structure in the production of ductile iron EN-GJS400-18.

This work describes the effect of austempering heat treatment on microstructure and mechanical properties of SAE 9260 steel. Steel samples, austenitized at 900 C for one hour, were isothermally heat-treated in the temperature range 300 to 350 C for different lengths of time. Microstructural characterization was carried out using optical and scanning electron microscopes. The microstructure of the austempered samples consisted of bainitic ferrite and retained austenite. The volume fraction of retained austenite was determined using X-ray diffraction. Isothermal heat treatment at 350 C for 20 min, resulted in a retained austenite content of around 38% in the microstructure. The increase in isothermal transformation temperature led to an increase in the fraction of retained austenite. Additionally, a good combination of strength and ductility was obtained in the samples with increased amounts of retained austenite.

The intensive progress of the various modern technologies (aeronautics, space exploration, nuclear energy, etc.) causes the need for the new structural materials operating in extreme conditions (high temperatures, aggressive media, high mechanical loads, etc.). However, the practice shows that tailoring of materials with the combination of all required properties is a rather hard task. As a result, the technique of coating used to protect refractory matrix from corrosion- and wear-resistance, radiation, etc. acquires special relevance.
A heat-resistant high-chromium alloy (Fe-45%Cr -4% Al) doped with the rare earth metals (0.25% La or Y), was found to be a protective material to the refractory matrix [Georgian Patent, P 3273, 24.06.2002, O.Mikadze, E.Kutelia et al.].
For the reliable protection of alloys of this system from long-term oxidation, it is necessary that the formed protective layer of Al2O3 would remain entirely solid and should not exfoliate when cooled. This problem can be solved by alloying the Fe-Cr-Al matrix with highly active, primarily rare earth elements.
In the present work, for similar purposes, the authors offer an iron-chromium alloy (up to 16% Cr) doped with Zr and Ce (Fe-16%Cr-5,0%Al-0,5%Zr -0,3%Ce). Adding of Ce changes the mechanism of formation of the protective oxide (Al2O3) layer at the metal-coating interface, resulting in the improved properties (adhesion, abrasion resistance, strength characteristics, etc.).
Positive influence of Ce on the formation of a protective oxide (Al2O3) layer is enhanced by its co-doping with Zr. Here an economic aspect of the technology is an important factor - it is significantly cheaper. The reduced chromium content (to 16%) makes it possible to provide air melting under flux and fabricate the product easy to forge, roll and process by cutting.
Ingots of the produced material were prepared in magnesite crucibles by induction melting under flux. Cylindrical samples (d=10mm and h=20 mm) were cut from the ingots rolled at T≈1,000°C. The samples were tested on heat resistance (at 1,200°C and 1,300°C in the air and at 1300±50°C in the atmosphere of combustion products of gaseous fuels);
The initial stages of oxidation were studied by the method of continuous weighing on the installation 'SETARAM'; long stages - by the method of periodic weighing.
The samples of the refractory matrix were coated by using the method of electron beam evaporation followed by condensation.
Morphology of the metal-coating interface layer was studied on the SEM (DSM-960, Zeiss, Germany).
The chemical composition and the concentration distribution of the elements in the scale determined by X-ray microanalysis (COMIBAX, CAMECA).
In this way, a special alloy (Fe-16,0%Cr-5,0%Al-0,5%Zr-0,3%Се) has been developed for protective coating of heat-resistant matrix; Doping of the alloy with Zr and Ce improves some tribological properties of the coatings; The developed alloy is recommended to protect operating units of power plants from degradation of their high-temperature properties.

The impact of two different types of refractory materials and layout in the life cycle of an electro-reduction Fe-Ni arc furnace, during regular production periods, with two different refractory lining materials, are described. It is shown the refractory lining consisting of a combination of magnesite bricks in vertical walls and graphite blocks in the slag levels has a life cycle about 3 times higher compared to the case when all walls were lined with magnesite bricks only. It was also found that although graphite blocks are very resistant to the molten slag, they are vulnerable to molten Fe-Ni alloy, which dilute carbon in it from graphite blocks. In order to avoid this, a modification has been proposed for the layout of the combined refractory lining that prevents the contact of graphite blocks with molten Fe-Ni when raising bath levels of molten metal inside the furnace occur, thus prohibiting carbon from dissolving into the molten alloy. This modification further increases the life cycle of the furnace refractory. This work is part of a long-term project undertaken in cooperation with FLOGEN Technologies Inc. In a subsequent future article, an overall physical simulation of all the above-mentioned phenomena will be presented.

During high strain rate deformation, some of the plastic work is transformed into heat. The lower thermal conductivity of Ti-6Al-4V alloys does not let the generated heat to escape easily thus producing an adiabatic system. Therefore, during deformation of Ti-6Al-4V alloy temperature increases called 'Adiabatic Heating'. Adiabatic heating contributes to flow softening in the stress-strain response of the material. Adiabatic heat rise and volume fraction of a phase in this two phase alloy has a strong influence on its hot deformation behavior. Hot compression tests were conducted on Gleeble 3500 thermo-mechanical simulator with cylindrical specimens in the temperature range of 700 - 1000 °C and strain rate range of 1 - 100 s-1 up to a true strain of 0.7. Experimental results show that the flow stress of Ti-6Al-4V alloy decreases with the increase in temperature and decrease in strain rate. Temperature rise due to adiabatic heating has been measured through K-type thermocouple. Adiabatic temperature rise contributes to increase in the volume fraction of a phase. Maximum temperature rise is observed to be 103 °C at strain rate of 100 s -1 and test temperature of 700 °C. Fraction increase in a phase due to adiabatic heating has been analyzed and an attempt has been made to co-relate it with Zener- Hollomon parameter (Z). The a volume fraction increases with temperature and strain rate. Z parameter and a volume fraction relation fits well by exponential relation for a given strain rate.

Increase of arsenic grade in the feed which is processed at different pyrometallurgical operations causes significant complication of the processes, because efficient capturing and disposal of the toxic arsenic-bearing dusts and slurries are required. The general way of arsenic recovery from pyrometallurgical products consists of arsenic transfer from these products to arsenites and arsenates which are slightly soluble in water, followed by burial at special deposits.
Low bulk weight of arsenites and arsenates along with their decomposition when contacting the atmosphere resulted in generation of water-soluble arsenic compounds, require considerable expenses for storage of these toxic wastes.
Arsenic transfer from arsenites and arsenates to more compact and less toxic product, ferric-arsenic alloy (ferric speiss) for example, allows reduction of the expenses and increase of ecological safety. This material which is almost insoluble in water and inert to atmospheric impacts can easily be stored at the open areas in a view of cast blocks. The research results presented in the paper proved the possibility and determined the conditions for efficient pyrometallurgical processing of different arsenic-bearing feed resulted in transfer of the arsenic to ferric speiss.

The innovation technology of assembling the space models of multidimensional phase diagrams from the entire totality of the geometric images corresponding to them is proposed. Basic principle of the design of the three-dimensional (3D) computer model of the ternary system T-x-y diagram is the assembling of 3D objects of its surfaces and phase regions. Finished T-x-y diagram 3D model allows to construct any arbitrarily assigned sections and to calculate mass balances of the coexisting phases in all stages of the crystallization for any arbitrarily assigned concentration. Moreover 3D computer models of phase diagrams are an effective tool for the verification of those experimentally constructed isothermal sections and isopleths, i.e., for checking the correctness of the interpretation of data, obtained from the experiment and the thermodynamic calculation. Such possibilities of 3D models can be seen on the examples of the using of the metal systems T-x-y diagrams - the bases of the creation of the materials, promising as the lead-free solders (Au-Ge-Sn, Ag-Ge-Sb, Ag-Au-Bi, Ag-Sb-Sn, Au-Bi-Sb, and so on). Their published data are not always deprived of contradictions. So, it is convenient to use the 3D computer models of T-x-y diagrams, designed according to the data of the different authors, for the agreement of the sections and for searching of contradictions in calculations or incorrect interpretation of experiment.
This work was been performed under the program of fundamental research SB RAS (project 0336-2016-0006), it was partially supported by the RFBR (projects 15-43-04304, 17-08-00875) and the RSF (project 17-19-01171).