Кафедра "Матеріалознавство"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/6927

Офіційний сайт кафедри http://web.kpi.kharkov.ua/mtrlvd

Від 2007 року кафедра має назву "Матеріалознавство", первісна назва – "Металознавство та термічна обробка металів".

Кафедра "Металознавство та термічна обробка металів" створена у 1932 році. Першим її очільником став доктор технічних наук, професор Олександр Володимирович Терещенко.

Кафедра являє собою одну із найстаріших в політехнічному інституті з підготовки інженерів-технологів-дослідників. Своїми науковими дослідженнями. з початку своєї діяльності, кафедра сприяла розвитку та удосконаленню технологій термічної та хіміко-термічної обробки деталей на підприємствах України».

Кафедра входить до складу Навчально-наукового інституту механічної інженерії і транспорту Національного технічного університету "Харківський політехнічний інститут".

У складі науково-педагогічного колективу кафедри працюють: 1 доктор технічних наук, 9 кандидатів технічних наук, 3 кандидата фізико-математичних наук, 1 доктор філософії; 1 співробітник має звання професора, 8 – доцента, 1 – старшого наукового співробітника.

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Influence of the Bias Potential and the Pressure of the Nitrogen Atmosphere on the Structure and Properties of Vacuum-arc Coatings Based on the AlCrTiZrNbV High-entropy Alloy
(Sumy State University, 2018) Sobol, O. V.; Andreev, A. A.; Gorban, V. F.; Postelnyk, A. A.; Stolbovoy, V. A.; Zvyagolskiy, A. V.
The effect of the constant bias potential (Ub) supplied to the substrate upon condensation and pressure of the nitrogen atmosphere (PN) on the elemental composition, growth morphology, texture, and physical-mechanical characteristics of vacuum-arc (AlCrTiVZrNb)Nx coatings is studied. It is established that with increasing Ub from – 110V to – 200V, the axis of preferential growth of crystallites of the fcc phase from [100] to [110] changes. Such a change is accompanied by a decrease in the hardness (H) and the ratio H/E (where E is the modulus of elasticity). The conditions for the formation of the preferential orientation of the crystallites (axial texture) of vacuum-arc (AlCrTiVZrNb)Nx coatings and the influence of texture on mechanical properties are discussed. It was established that the change in PN in the range Torr basically allows to vary the degree of filling of the coating with nitrogen atoms. Based on the revealed regularities, the conditions for achieving high hardness for vacuum-arc coatings of nitrides AlCrTiVZrNb high-entropy alloy are substantiated. Because of the presence in the alloy of elements with a relatively low heat of nitride formation, in order to achieve high hardness, it is necessary to use deposition conditions with relatively low energy of bombarding atoms. The use of a low Ub = –110 V at the highest pressure Torr allows achieving an superhard state with a hardness of 44 GPa.
Structural Engineering of the Growth of Crystallites with a Predominant Orientation in Bilayer Multi-Period Vacuum arc Nitride Coatings
(Sumy State University, 2018) Sobol, O. V.; Mygushchenko, R. P.; Postelnyk, A. A.; Onoprienko, E. V.; Syrenko, T. O.; Men'shikov, A. G.; Zvyagolskiy, A. V.
The effect of the MeN (Me-Cr, Mo, Zr) layer composition in multiperiod vacuum-arc (TiAlSi) N / MeN coatings with a nanoscale layer thickness on the predominant orientation of crystallite growth in layer s and hardness was studied. It was found that phases with a cubic crystal lattice (structural type NaCl) in the layers of all types (TiAlSi)N/MeN coatings are formed, although for the MoN phase under equilibrium conditions a hexagonal crystal lattice is preferred. The interrelation between the structure of MeN and (TiAlSi)N layers is revealed, as well as the effect of the structural state on the coating hardness. Defining influence of the MeN layer on the formation of three structural states types was found: with a preferential crystallite growth with the texture axis [111]; with the texture axis [100]; the formation of a non-textured state. The highest hardness of 47.8 GPa was achieved in the (TiAlSi)N/ZrN multilayer coating with the texture axis [111].
The Influence of Layer Thickness and Deposition Conditions on Structural State of NbN/Cu Multilayer Coatings
(Sumy State University, 2019) Sobol, O. V.; Andreev, A. A.; Meylekhov, A. A.; Postelnyk, A. A.; Stolbovoy, V. A.; Ryshchenko, I. M.; Sagaidashnikov, Yu. Ye.; Kraievska, Zh. V.
The influence of the main physical and technological factors of structural engineering (layer thickness, nitrogen atmosphere pressure and bias potential) on the structural-phase state of the NbN/Cu coatings was studied. It was established that with an increase in the thickness of niobium nitride layers from 8 to 40 nm (in the NbN/Cu multilayer composition), the phase composition changes from the metastable NbN (cubic crystal lattice, NaCl structural type) to the equilibrium ε-NbN phase with a hexagonal crystal lattice. At low pressure PN = 7·10 – 4 Torr in thin layers (about 8 nm thick), regardless of the Ub, the NbN phase is formed. The reason for the stabilization of this phase can be the uniformity of the metallic fcc crystal lattice of the δ-NbN phase with the Cu crystal lattice. As the pressure increases from РN = 7·10 – 4 Torr to 3·10 – 3 Torr, a more equilibrium ε-NbN phase with a hexagonal crystal lattice is formed. An increase in the bias potential during deposition from – 50 V to – 200 V mainly affects the change in the preferred orientation of crystallite growth. In thin layers of the NbN phase (about 8 nm), a crystallite texture with the [100] axis is formed. In layers with a thickness of 40-120 nm, crystallites of the NbN phase are predominantly formed with a hexagonal (004) plane parallel to the growth plane. At the greatest layer thickness (more than 250 nm), the NbN phase crystallites are predominantly formed with a (110) hexagonal lattice plane parallel to the growth plane. The results obtained show great potential for structural engineering in niobium nitride when it is used as a constituent layer of the NbN/Cu multilayer periodic system.
Structural Engineering Multiperiod Coating ZrN/MoN
(Sumy State University, 2016) Sobol, O. V.; Meylekhov, A. A.; Stolbovoy, V. A.; Postelnyk, A. A.
Using the method of structural engineering by changing the thickness of the layers in a multiperiod ZrN/MoN system investigated the effect of the phase-texture state of the crystallites and their size on the hardness of the vacuum-arc coating. Is revealed a determining influence on the formation of ZrN layers preferential orientation growth [100] axis with a small layer thickness 7-20 nm (the deposition of 3 to 10 seconds). At high layer thickness determines the texture [311] crystallites are - Mo2N phase formed in the Mo-N layers. Pulsed high-voltage stimulation without changing the type of structural states for different layer thicknesses, leads to partial disorientation texture in thick layers. Hardness of coating with thick (80 nm) layers is 35-37 GPa. In small thickness layers pulse stimulation of atoms motility causes the formation of a planar structure with an average crystallite size of 4-9 nm in the layers, which is accompanied by increased hardness of up to 44 GPa.
The Influence of Layers Thickness on the Structure and Properties of Bilayer Multiperiod Coatings Based on Chromium Nitride and Nitrides of Transition Metals Ti and Mo
(Sumy State University, 2018) Sobol, O. V.; Meylekhov, A. A.; Mygushchenko, R. P.; Postelnyk, A. A.; Tabaza, Taha A.; Al- Qawabah, Safwan M.; Gorban, V. F.; Stolbovoy, V. A.
The influence of the layers thickness of bilayer multi-period coatings of the CrNx/MoNx and CrNx/TiNx systems on their phase-structural state, substructure, stress-strain state and mechanical properties was studied using methods of precision structural analysis in combination with computer simulation of implantation processes during particle deposition. It is established that a two-phase structure of CrN and-Mo2N phases of the structural type NaCl is formed in the multi-period coatings of the CrNx/MoNx system with a nanometer thickness of the layers. Because of the small difference in periods (less than 0.5 %) for Λ = 20 nm, the layers form a coherent interlayer interface. The use of small Ub – 20 V during deposition makes it possible to avoid significant mixing at interlayer (interphase) boundaries even at the smallest Λ = 10 nm. Nitride layers formed under conditions of vacuum arc deposition are under the action of compressive stresses. In the СrNх/TiNх system, because of the relatively large discrepancy between periods (more than 2.5 %), during the formation of the same structural components in the layers (CrN and TiN phases of the structural type NaCl), the epitaxial growth with period adjusting does not occur, even for the smallest Λ = 10 nm. The action of the deformation factor at the interphase boundary allows achieving an ultrahard state (with a hardness of about 50 GPa), which causes a relatively low friction coefficient. The obtained results on the formation of phase-structural states with the nanoscale thickness of layers of multi-period nitride coatings are explained from the position of minimization of surface energy and deformation energy.
А Computer Simulation of Radiation-Induced Structural Changes and Properties of Multiperiod ZrNₓ/MoNₓ System
(Sumy State University, 2017) Sobol, O. V.; Meylekhov, A. A.; Bochulia, T. V.; Stolbovoy, V. A.; Gorban, V. F.; Postelnyk, A. A.; Shevchenko, S. M.; Yanchev, A. V.
Influence of the period value Λ (at different negative potential Ub that supplied during deposition) on phase composition, structure, stress-strain state and hardness of multiperiod coatings ZrNₓ/MoNₓ is investigated by using complex methods of validation structural state at combined with microindentation. Formation in layers ZrNx and MoNx the phases with cubic lattice and preferred orientation of crystallites with axis [100] is established. Stress-strain state of compression with increasing Ub is amplified and reaches maximum value (– 6.7 GPa) at Λ = 20 nm and Ub – 110 V. Hardness of coating increases with decreasing Λ from 300 to 20 nm. Coatings that obtained with Λ = 20 nm and Ub – 110 V have the highest hardness 44 GPa. Relaxation of structural compressive stresses and decreasing hardness is happening at smaller Λ and larger Ub – 110 V (as a result of radiation-stimulated forming defect and mixing). Data of computer modeling of defectiveness at atomic level at bombardment of ions that accelerated in field Ub are used to explain the results.
Structure and Properties of Vacuum Arc Single-Layer and Multiperiod Two-Layer Nitride Coatings Based on Ti(Al):Si Layers
(Sumy State University, 2017) Beresnev, V. M.; Sobol, O. V.; Pogrebnjak, A. D.; Lytovchenko, S. V.; Stolbovoy, V. A.; Srebniuk, P. A.; Novikov, V. Ju.; Doshchechkina, I. V.; Meylehov, A. A.; Postelnyk, A. A.; Nyemchenko, U. S.; Mazylin, B. A.; Kruhlova, V. V.
The paper provides an analysis of impact of deposition conditions on structural and phase state and thermal stability of vacuum arc coatings based on Ti(Al):Si layers. We studied single-phase single-layer coatings, and multiperiod bilayer coatings with second phase nitride interlayers of one of the following three metals: Mo, Cr or Zr. It was established that hexagonal and cubic lattices may form in the coatings when transition to the cubic lattice occurs with Al content of about 25 at. %. Presence of second nanoscale (7-8 nm) layers in bilayer multiperiod compositions, which consist of one nitride from CrNx, MoNx or ZrNx group, does not change the type of lattice in [Ti(Al):Si]Nx layers. Also, an fcc lattice with a strong or weak texture [111] forms in CrNx and ZrNx layers, while crystallites with hexagonal lattice form in MoNx layers. High-temperature annealing at 700 °С during 40 minutes leads to a significant (by 23 % or up to H 47.56 GPa) increase in microhardness of coating of the [Ti(Al)]Nx/ZrNy system due to formation of a nano-size structure with an average size of crystallites of 3.6 nm in [Ti(Al)]Nx layers, and 6.3 nm in ZrNx layers.
The use of plasma-based deposition with ion implantation technology to produce superhard molybdenum-based coatings in a mixed (C2H2+N2) atmosphere
(2018) Sobol, O. V.; Andreev, A. A.; Mygushchenko, R. P.; Beresnev, V. M.; Meylekhov, A. A.; Postelnyk, A. A.; Kravchenko, S. A.; Tabaza, Taha. A.; Al-Qawabah, Safwan M.; Al-Qawabeha, Ubeidulla F.; Stolbovoy, V. A.; Serdyuk, I. V.; Kolesnikov, D. A.; Kovaleva, M. G.
The influence of the pressure of a mixed gaseous atmosphere (80%C2H2+20%N2) and the supply of a high-voltage negative potential in a pulsed form on the elemental and phase composition, structure and physico-mechanical characteristics of the vacuum-arc molybdenum-based coatings. It is shown that in the temperature deposition range 400…550 °С as a result of plasma-chemical reactions, the maximum nitrogen atoms content in the coating does not exceed 1.5 at.%. It is found, that at the maximum pressure of РC2H2+N2= 2.3∙10-1 Pа when the γ-MoC phase is formed, an superhard state of 50.5 GPa (at a constant potential -200 V, without additional high-voltage pulse action) and 51.1 GPa (at a constant potential -200 V, with additional high-voltage pulse action) is reached.
Structure and mechanical properties of nitride multilayer systems on the basis of high entropy alloys and transition metals of group VI
(2016) Nyemchenko, U. S.; Beresnev, V. M.; Sobol, O. V.; Lytovchenko, S. V.; Stolbovoy, V. A.; Novikov, V. Ju.; Meylekhov, A. A.; Postelnyk, A. A.; Kovaleva, M. G.
The influence of technological parameters of obtaining on the possibilities of structural engineering and mechanical properties of multilayer compositions of the layers of nitrides of high entropy alloy Ti-Zr-Nb-Ta-Hf and of transition metal (Group IV) nitrides has been analysed. It is shown that with the bias potential Ub lesser than -150 V was applied to the substrate during deposition, a two-phase state with the preferred orientation of the crystallites can be reached in multilayer coatings with the thickness of the layers of 50 nm. This leads to high hardness (up to 44 GPa) and to high adhesion strength (critical load up to 125 N) as well as to low wear (with a counterbody Al ₂O₃, and with steel Ac100Cr6). High-temperature annealing (700 ⁰C) of such coatings leads to enhanced texture as a result of atomic ordering, which is accompanied by increasing of hardness up to 59 GPa. The supply of bias potential exceeding 150 V, followed by a substantial mixing at the interphase boundary results in disorientation and improves dispersion of the crystallites, reduces hardness and wear resistance. High temperature annealing of such structures leads to reduction of their mechanical properties.