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  1. 42 Acta Physica Polonica A

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  1. 8 Pogrebnjak A.

  2. 7 Beresnev V.

  3. 6 Bondar O.

  4. 5 Sen U.

  5. 4 Kolesnikov D.

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1
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Effects of Third-generation LED LCU on Nanomechanical Properties of Orthodontic Adhesives

100%
Bilgic F., Altan H., Akinci Sözer Ö., Arslanoglu Z., Kale E., Özarslan S.
Acta Physica Polonica A
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2017
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vol. 132
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issue 3
697-701
EN
The aim of this study was to compare the hardness and elastic modulus of orthodontic adhesives cured with different light-curing units, based on light-emitting diodes. Standardized samples of orthodontic adhesives, Transbond™ XT, Opal® Bond™ and Light Bond™ were prepared in cylinder blocks and cured for three seconds with Valo Ortho LED (Ultradent Products, South Jordan, Utah) and Valo LED High-Power Mode. After grinding and polishing, specimens were stored in distilled water at 37°C for one day. Specimens were investigated using nanoindenter. Employment of Valo Ortho unit has resulted in significantly higher elastic modules for Transbond™ XT (p=0.041). The highest nanohardness and elastic modules were measured for Transbond™ XT cured with Valo Ortho (9.47 GPa; 81.85 GPa, respectively) and lowest for Opal® Bond™ for both Valo Ortho (0.44 GPa; 14.52 GPa, respectively) and Valo High-Power groups (0.44 GPa; 11.84 GPa, respectively).
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Nanomechanical Properties of Different Dental Restorative Materials

100%
Altan H., Bilgic F., Arslanoglu Z., Kale E., Köroğlu Kale A., Altan A., Sahin O.
Acta Physica Polonica A
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2016
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vol. 130
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issue 1
394-396
EN
The aim of this study is to determine the hardness and roughness of glass ionomer cement, glass carbomer, and compomer by nanoindentation. Three different dental restorative materials: glass ionomer cement, glass carbomer cement, and compomer were used. Disc specimens (10 mm × 1 mm) were prepared from each material using teflon mold. All specimens were light cured according to the manufacturer's instructions. The specimens were then mounted in polyacrilic resin. After grinding and polishing the specimens were stored in distilled water at 37°C for 1 day. The specimens were investigated using nanoindenter. The highest nanohardness was measured for glass ionomer cement and the lowest for glass carbomer. Regarding roughness, glass ionomer cement and compomer showed the highest mean values. Glass ionomer cement and compomer exhibited similar nanomechanical properties. Glass carbomer had superior ability to be polished up.
3
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Structure and Properties of Fe-Ni-Al-Si Alloys Produced by Powder Metallurgy

100%
Novák P., Mejzlíková L., Hošek V., Martínek M., Marek I., Michalcová A.
Acta Physica Polonica A
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2012
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vol. 122
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issue 3
524-527
EN
Reactive sintering powder metallurgy is a simple alternative to conventional melting and powder metallurgy processes. During this process, pressed powder mixture of pure metals or other precursors is transformed into bulk intermediary phases by thermally activated in situ reaction. This process was previously tested on Fe-Al and Fe-Al-Si alloys. Positive effect of silicon on the reactive sintering behaviour was determined, leading to the development of novel carbon-free high-silicon FeAl20Si20 alloy (given in wt%). In this work, the effect of nickel on the pressureless reactive sintering of Fe-Al-Si pressed powder mixtures was studied. To explain the nickel influence, differential thermal analysis was utilized. Microstructure, phase composition and porosity of the FeAl20Si20Nix (x = 0, 5, 10, 20 wt%) alloys was described. Hardness, wear resistance, high-temperature oxidation resistance and thermal stability were evaluated as functions of nickel content. Results showed that porosity decreases with growing nickel content down to less than 3 vol.%. Oxidation rate of these alloys is more than 10 times lower than that of original FeAl20Si20 alloy. Thermal stability and abrasive wear resistance of these alloys is also superior to Fe-Al and Fe-Al-Si materials.
4
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Structure and Physicomechanical Properties of Nanostructured (TiHfZrNbVTa)N Coatings after Implantation of High Fluences of N⁺ (10¹⁸ cm¯²)

100%
Pogrebnjak A., Bondar O., Borba S., Piotrowska K., Boiko O.
Acta Physica Polonica A
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2017
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vol. 132
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issue 2
217-221
EN
New classes of high-entropy alloys, which consist of at least 5 main elements with atomic concentrations 5-35 at.%, are under great interest in modern material science. It is also very important to explore the limits of resistance of high-entropy alloy nitrides to implantation by high-energy atoms. Structure and properties of nanostructured multicomponent (TiHfZrNbVTa)N coatings were investigated before and after ion implantation. We used the Rutherford backscattering, scanning electron microscopy with energy dispersive X-ray spectroscopy, high resolution transmission electron microscopy and scanning transmission electron microscopy with local microanalysis, X-ray diffraction and nanoindentation for investigations. Due to the high-fluence ion implantation (N⁺, the fluence was 10¹⁸ cm¯²) a multiphase structure was formed in the surface layer of the coating. This structure consisted of amorphous, nanocrystalline and initial nanostructured phases with small sizes of nanograins. Two phases were formed in the depth of the coating: fcc and hcp (with a small volume fraction). Nitrogen concentration reached 90 at.% near the surface and decreased with the depth. Nanohardness of the as-deposited coatings varied from 27 to 34 GPa depending on the deposition conditions. However, hardness decreased to a value of 12 GPa of the depth of the projected range after ion implantation and increased to 23 GPa for deeper layers.
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Fabrication and Research of Superhard (Zr-Ti-Cr-Nb)N Coatings

100%
Bondar O., Postolnyi B., Kravchenko Y., Shypylenko A., Sobol O., Beresnev V., Kuzmenko A., Zukowski P.
Acta Physica Polonica A
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2015
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vol. 128
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issue 5
867-870
EN
This work presents the results of (Zr-Ti-Cr-Nb)N superhard coatings research. The samples were fabricated by the vacuum-arc deposition method (Arc-PVD). Structure, composition and properties of these coatings were studied. The study of coatings was carried out using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Hardness measurements and adhesion tests were performed. The coatings thickness was up to 6.2 μ m, nanocrystallites sizes ranged from 4 to 7.3 nm. Values of hardness and cohesive strength were H=43.7 GPa and L_{C}=62.06 N, respectively. The optimal conditions for coating deposition were found.
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The Effects of Austempering and Induction Hardening on the Wear Properties of Camshaft Made of Ductile Cast Iron

100%
Karaca B., Şımşır M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
448-452
EN
The aim of this study is to investigate the effects of heat austempering and induction hardening on the wear properties of GGG60 ductile cast iron for camshaft production. For this purpose, camshafts have been produced by sand mould casting method. Fe-Si-Mg alloy has been used for inoculation process to achieve iron nodulization. The casting has been done between 1410-1420°C. The casted camshafts have been austenitized at two different temperatures (800 and 900°C) and time intervals (60 and 90 min) under controlled furnace atmosphere. The austenitized camshafts have been quenched into the molten salt bath at 360°C, held there for 90 min and then cooled in air. This way, austempering heat treatment has been applied. After that, surface hardening process was conducted using induction hardening machine with medium frequency. Microstructure of camshafts has been examined by optical methods and mechanical tests have been performed. Results show that austempering heat treatment increases the wear resistance of camshaft, compared to as-cast condition. Wear resistance of the camshaft increases with increasing austenitizing temperature, time and with induction hardening. The lowest weight loss of 0.62 mg has been obtained for the induction hardened camshaft austenitized at 900°C for 90 min.
7
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Structural Characterization of Boro-Titanized AISI 1040 Steel

100%
Kon O., Pazarlıoğlu S., Durmaz M., Sen U., Sen S.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
1211-1213
EN
In this study, boro-titanizing treatment was applied to AISI 1040 steel. In the coating treatment, steel samples were pre-boronized in a slurry salt bath consisting of borax, boric acid and ferro-silicon at 900°C for 2 h, then titanized by thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-titanium, ammonium chloride, alumina and naphthalene at 1000°C for 1-4 h. The coated samples were characterized by X-ray diffraction analysis (XRD), scanning electron microscope (SEM), glow discharge optical emission spectroscopy (GDOES) and micro-hardness tests. Coated layer formed on the pre-boronized AISI 1040 steel was compact and homogeneous. X-ray studies showed that the phases formed on the steel surfaces are TiB₂, TiC, TiN and Fe₂B. The depth of the coating layer ranged from 3.41± 0.47 μm to 6.59± 0.51 μm, depending on treatment time. A higher treatment time resulted in a thicker boro-titanized layer. The average hardness of the coating layer was 4527± 284 HV_{0.005}.
8
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The Properties of Cr-Al-N Based Coatings Formed on AISI D2 Steel by Thermo-Reactive Diffusion Technique

80%
Kılınc B., Sen U., Sen S.
Acta Physica Polonica A
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2013
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vol. 123
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issue 2
271-273
EN
In this study, chromium aluminum nitride coating was applied on pre-nitrided AISI D2 steel by the thermo-reactive deposition technique in a powder mixture consisting of ferrochromium, aluminum, ammonium chloride, and alumina at 1000C for 2 h. Steels were gas nitrided for the purpose to enrich the surfaces with nitrogen of the steels in a nitrogen and ammonia atmosphere at 560C for 8 h. The effect of aluminum content in the powder mixture on the Cr-Al-N layer properties was investigated. The coated samples were characterized by X-ray diffraction analysis, scanning electron microscope, and micro-hardness tests. Chromium aluminum nitride layer formed on the pre-nitrided AISI D2 steel was compact and homogeneous. Electron dispersive spectrometer results showed that coating layer includes chromium, aluminum, and nitrogen. X-ray studies showed that the phases formed in the coating layers on the steel surfaces are Cr_2N, (Cr,Fe)_2N_{1-x}, AlN, and Fe_2N. The depth of the Cr-Al-N layer ranged from 10.01 ± 1.2 to 13.2 ± 1.7 μm, depending on the aluminum content. The hardness of the coated layers produced on AISI D2 steel are changing from 1743 ± 150 HV_{0.01} to 2067 ± 160 HV_{0.01} depending on bath compositions.
9
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Powder Metallurgy Preparation of Co-Based Alloys for Biomedical Applications

80%
Marek I., Novák P., Mlynár J., Vojtěch D., Kubatík T., Málek J.
Acta Physica Polonica A
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2015
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vol. 128
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issue 4
597-601
EN
Co-based alloys represent very important group of materials used for medical applications. Currently, fabrication of these materials is preferentially done by casting or forming. Production by powder metallurgy techniques is less common. However, powder metallurgy fabrication of these alloys brings advantages such as reduced machining, possibility of alloying by high-melting elements, preparation of nanocrystalline materials with enhanced mechanical properties or producing of porous alloys with improved ability to integrate into issues. In this work, our attention was focused on fundamental preparation of an CoCrMo alloy by two methods of powder metallurgy. In the first method, pure metallic powders were mixed, pressed and sintered in vacuum furnace. The second applied technology consisted of mechanical alloying using planetary ball mill and compaction by spark plasma sintering technique. A series of samples was prepared under various conditions by these procedures. Dependence of microstructure, phase composition and mechanical properties of prepared samples on fabrication conditions (milling parameters, sintering temperature etc.) was studied. Obtained results were compared with properties of commercial cast cobalt alloy used for medical applications.
10
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Long-Range Effect in Ion-Implanted Titanium Alloys

80%
Budzynski P., Sielanko J.
Acta Physica Polonica A
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2015
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vol. 128
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issue 5
841-844
EN
Surface modification of titanium alloy (Ti6Al4V) by nitrogen ion implantation and ion beam-assisted deposition (C, N) was investigated. The depth distribution of implanted nitrogen atoms was analysed using the Rutherford backscattering technique. Nitrogen implantation reduces the coefficient of friction and wear. A better effect can be obtained when nitrogen implantation is combined with carbon deposition. Based on the changes in the coefficients of friction and wear as well as profilograms of wear tracks, the improvement of the tribological properties was found at a depth exceeding nearly 5 times the range of the implanted nitrogen ions. Identification of the long-range effect for Ti6Al4V alloy was performed on the basis of tribological analyses. This study is a continuation of research conducted for AISI 316L and H11 steel.
11
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Influence of Parameters on Tribological Behaviour of E-Glass Fiber Reinforced Epoxy Composites

80%
Ozsoy N., Ozsoy M., Mimaroglu A.
Acta Physica Polonica A
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2015
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vol. 128
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issue 2B
B-55-B-58
EN
E-glass fiber reinforced epoxy composites were fabricated by hand lay up method and tested for investigating tribological behaviours. Wear behaviours of composites 0°, 90° and [0°/90°] oriented were investigated by pin on disc wear tester device for a constant distance (1000 m) and the design of experiments approach using the Taguchi method was employed. The tests were conducted sliding against a steel disc (60 HRC) under different sliding and loading conditions. Signal to noise ratio and analysis of variance (ANOVA) were used to investigate the influence of parameters on the wear rate and coefficient of friction.
12
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Investigation of Nanoscale TiN/MoN Multilayered Systems, Fabricated Using Arc Evaporation

80%
Pogrebnjak A., Bondar O., Abadias G., Eyidi D., Beresnev V., Sobol O., Postolnyi B., Zukowski P.
Acta Physica Polonica A
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2015
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vol. 128
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issue 5
836-840
EN
Using the vacuum-arc evaporation method we fabricated periodic multilayered TiN/MoN structures with different bilayer periods λ ranging from 8 to 100 nm. We found that molybdenum nitride and titanium nitride layers grown on steel show local partial epitaxy and columnar growth across interfaces. A molybdenum-titanium carbide interlayer was evidenced between the substrate and the multilayer. Molybdenum nitride and titanium nitride layers contain small (5÷30 nm) grains and are well crystallized with (100) preferred orientation. They were identified as stoichiometric fcc TiN and cubic γ-M₂N. Non-cubic molybdenum nitride phases were also detected. The hardness of the obtained structures achieved great values and maximal hardness was 31÷41.8 GPa for the multilayered structure with a 8 nm period. Hardness of the obtained coatings is 25÷45% higher in comparison with the initial single-layer nitride coatings, plasticity index of multilayered structure is 0.075.
13
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Effect of Aluminum Addition to Nb-Al-C-N Coatings on AISI M2 Steel Obtained by Thermo-Reactive Deposition Technique

80%
Abakay E., Sen S., Sen U.
Acta Physica Polonica A
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2016
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vol. 129
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issue 4
653-655
EN
In this study, aluminum-doped (1 and 2 wt.%) and Al-free niobium carbo-nitride coatings were applied to the surface of AISI M2 high speed steel using the process of thermo-reactive deposition technique (TRD) at 1000°C during 1-4 h. The obtained coatings were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis and micro hardness test. Nb-Al-C-N layers were compact and homogeneous. X-ray diffraction analysis has shown that the major phases formed in the coating layer are Nb₂CN and NbN. The depth of the coating layer had increased with the treatment time and ranged from 6.65 to 9.05 μm. The measured values of the hardness of the coating layers were ranging between 2136 and 2636 HK_{0.005}.
14
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Multicomponent (Ti-Zr-Hf-V-Nb)N Nanostructure Coatings Fabrication, High Hardness and Wear Resistance

80%
Pogrebnjak A., Beresnev V., Kolesnikov D., Bondar O., Takeda Y., Oyoshi K., Kaverin M., Sobol O., Krause-Rehberg R., Karwat C.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
816-818
EN
First results in the field of synthesis and research of the multicomponent (Ti-Zr-Hf-V-Nb)N nanostructured coatings are presented in the paper. Influence of processes of spinodal segregation and mass-transfer on single-layered or multilayered crystal boundary (second phase) forming were explored. Superhard nanostructured coatings were investigated before and after annealing at the temperature 600°C using unique methods (slow positron beam, proton microbeam particle induced X-ray emission-μ, Rutherford backscattering-analysis, scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction analysis was performed using DRON-4 and nanoindentor). Diffraction spectra were taken point-by-point, with a scanning step 2Θp=0.05 to 0.1°. We detected that positron trapping by defects was observed on the nanograins boundaries and interfaces (vacancies and nanopores which are the part of triple and larger grain's boundary junction). The 3D distribution maps of elements obtained by the proton microbeam (particle induced X-ray emission-μ) together with the results obtained by slow positron microbeam gave us comprehensive information about physical basis of the processes, connected with diffusion and spinodal segregation in superhard coatings.
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Optimization of Surface Properties of Shot Peened TI6AL4V Alloy

80%
Yıldıran Y., Avcu E., Sınmazçelik T.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
984-986
EN
As an important surface treatment method, shot peening (SP) is widely used in automotive and aerospace industries in order to improve surface properties. In the present study SP was performed on the α-β titanium alloy Ti6Al4V under various parameters (particle impingement angle, particle acceleration pressure and particle size) by using a specially designed shot peening test rig. It is aimed to optimize surface roughness and hardness of the shot peened Ti6Al4V alloy under various parameters. In order to achieve this goal shot peened samples were investigated in detail by using a non-contact laser optical profilometer and surface hardness of the samples was measured by using a micro-hardness instrument. The surface roughness values, 3D surface morphologies and micro-hardness of the samples were obtained and examined. The results show that particle impingement angle, particle acceleration pressure and particle size dramatically affect the surface properties of the Ti6Al4V alloy.
16
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Mechanical Properties of Boronized AISI 316, AISI 1040, AISI 1045 and AISI 4140 Steels

80%
Calik A., Sahin O., Ucar N.
Acta Physica Polonica A
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2009
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vol. 115
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issue 3
694-698
EN
In this study, some mechanical properties of borided and unborided four steels were investigated. Boronizing of steels was performed by powder pack method at 1210 K for 4 h. The hardness of borides, boride layer thickness and room temperature tensile properties were measured and it was observed that hardness and tensile properties strongly depend on chemical composition of steels. In addition, the effect of a notch on impact behavior was examined by conducting the Charpy tests on borided and unborided steels. The greatest notch toughness was found for a steel AISI 316 with a microstructure consisting of different C, Ni and Cr chemical composition compared to AISI 1040, 1045 and 4140 steels.
17
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Surface Properties of Me/Si Structures Prepared by Means of Self-Ion Assisted Deposition

80%
Tashlykov I., Żukowski P., Mikhalkovich O., Baraishuk S.
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vol. 125
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issue 6
1306-1309
EN
In this paper a composite structure, topography, wettability and nanohardness of a (100) Si surface modified by means of ion-assisted deposition of metal (Me) coatings in conditions of a self-irradiation are discussed.
18
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Effect of Thermal Treatment on the Structure and Mechanical Properties of Coatings Based on (Ti, Hf, Nb, Si)N

80%
Pogrebnjak A., Komarov F., Sobol O., Kaverina A., Shypylenko A., Karwat C.
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vol. 125
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issue 6
1312-1316
EN
Current paper presents the results of investigating of nanostructured cathode arc vacuum evaporation coatings, based on (Ti, Hf, Nb, Si)N. Several methods of the structural and elemental analysis were used: proton microbeam, nano- and micro-electron beam, X-ray diffraction analysis. To determine tribological properties (scratch resistance, adhesive and cohesive strength) of the coatings, scratch testing were conducting. Influence of thermal annealing at temperatures 300, 500, 800, 1000C on elemental composition, microstructure, residual stress, phase composition, profiles of atomic distribution in the coatings were investigated.
19
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Influence of Deposition Parameters and Thermal Annealing on the Structure and Properties of Nitride Coatings (TiHfZrVNb)N

80%
Pogrebnjak A., Abadias G., Chartier P., Bondar O., Yakuschenko I., Takeda Y., Krause-Rehberg R., Kolesnikov D., Beresnev V., Partyka J.
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vol. 125
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issue 6
1296-1299
EN
Results of structure, phase composition, physical and mechanical properties and tribological properties investigations of nitride high-entropy coatings (TiZrHfVNb)N are presented in the paper. Proton microbeam (μ-PIXE), X-ray diffraction method, including method of X-ray strains measurements, energy dispersive X-ray spectroscopy and scanning electron microscopy analysis, microhardness testing and nanoindentation were used. Thermal annealing (t=600°C) influence on defect profiles, structure and element distribution in the coatings was investigated. It was found that thermal treatment of coatings leads to changing of defect profiles and to element redistribution. Also we can say that it influences less on grain size changing. Investigated (TiZrHfVNb)N coatings demonstrate high values of hardness and excellent wear resistance.
20
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Microhardness and the Young Modulus of Thin, MBE-Grown, (Sn,Mn)Te Layers Containing up to 8% of Mn

80%
Adamiak S., Zięba M., Minikayev R., Reszka A., Taliashvili B., Szuszkiewicz W.
Acta Physica Polonica A
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2017
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vol. 132
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issue 2
347-350
EN
The thin layers of (Sn,Mn)Te solid solution were grown by molecular beam epitaxy onto (111)-oriented BaF₂ substrates and characterized by scanning electron microscopy, atomic force microscopy, energy dispersive X-ray spectrometry, and X-ray diffraction methods. The epitaxial character of the growth was confirmed. All the layers exhibited a regular (fcc) structure of the rock-salt type and were (111)-oriented, their thickness was close to about 1 μm. The layers contained up to 8% of Mn. The microhardness and the Young modulus values were determined by the nanoindentation measurements. The Berkovich type of the intender was applied, the maximum applied load was equal to 1 mN. The results of measurements demonstrated a lack of the composition dependence of the Young modulus value. A slight increase of the microhardness value with an increasing Mn content in the (Sn,Mn)Te solid solution was observed.
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