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  1. 66 Acta Physica Polonica A

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  1. 4 Hadzima B.

  2. 4 Král R.

  3. 4 Minárik P.

  4. 4 Çalışkan F.

  5. 3 Akarslan F.

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1
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Effects of the Wind Speed and the Material Emplacement on the Output Signal of PZT Piezoelectric Energy Harvester

100%
Demir F., Anutgan M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
362-365
EN
In this study the electrical signal produced from wind energy through a (Pb_{x}X_{1-x})(Zr_{y}Ti_{z}Y_{1-y-z}) piezoelectric transducer is analyzed. The material is placed onto a metal frame at different positions and voltage outputs of each are compared at different wind flow speeds and load resistance values. The absorption of the wind energy is tested by connecting a polyurethane material in parallel and perpendicular to the wind flow direction. The use of that material with optimum emplacement condition is shown to increase the voltage output by at least two orders of magnitude, where the maximum voltage output obtained is 13 V, and the maximum power is 338 μW.
2
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Gamma-C₂S Synthesis from Fly Ash of Fluidize-Bed Boiler for CO₂ Capture

100%
Na S., Kang S., Lee S., Song M.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
1282-1285
EN
This paper describes the CO₂ capture performance of cement blended paste incorporating gamma-dicalcium silicate (gamma-C₂S) made with industrial by-products, by taking into consideration of effect of CaCO₃, fly ash replacement ratio under the sintering process. X-ray diffraction method was conducted in order to quantitatively investigate the gamma-C₂S content. CO₂ capture performance of mortar sample incorporating gamma-C₂S was investigated by means of compressive strength test using accelerated carbonation chamber. The experimental results revealed that the kind of CaCO₃ would affect the affect the formation of gamma-C₂S after the sintering with respect to the XRD-Rietveld analysis. Moreover, it is confirmed that compressive strength of mortar sample incorporating gamma-C₂S has the same tendency at curing age of 3, 7 and 28days. Blended mortar sample made with 10 wt.% replacement ratio of gamma-C₂S had high compressive strength value compared to normal mortar sample, therefore, incorporating gamma-C₂S had a positive effect on the compressive strength after accelerated carbonation. Finally, the waste foundry sand powder may be alternative to produce gamma-C₂S.
3
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The Grey-Based Taguchi Method: Optimisation of Drilling of Hybrid Aluminum Matrix Composites

100%
Ay M., Altunpak Y., Hartomacıoğlu S.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
551-554
EN
The aim of this study was to investigate the influence of cutting parameters and effect of graphite rate on cutting force and surface roughness in drilling of Al/20%SiC/5%Gr, Al/20%SiC/7.5%Gr and Al /20%SiC/10%Gr hybrid composites, fabricated by vortex method. The drilling tests are conducted with diamond-like-carbon coated cutting tools. The Grey relational analysis based Taguchi optimization method was selected to determine the optimum cutting conditions. The results show that the spindle speed (4500 rpm), the rate of graphite (10%) and feed (0.1 mm/rev) were found to be significant parameters for surface roughness and cutting force. The predicted values from the developed model and experimental values are found to be very similar in this study.
4
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Vibrating Subsystems of Freight Wagons and Their Beam Models

100%
Buchacz A.
Acta Physica Polonica A
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2017
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vol. 131
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issue 1
62-63
EN
The application of analysis of transverse vibrating subsystem of complex microelectromechanical systems by means of the exact and approximate methods were the main purposes of work to solve the task of assignment of frequency-modal analysis and characteristics of mechatronic system. The problems concerned of piezoelectricity and electrostriction and classical and nonclassical methods to solve this problem have been used to obtain the dynamical characteristics in the Gliwice Research Centre. Other diverse problems have been modeled by different methods and next they were examined and analysed. Analysing the diagrams of characteristics of confirmed system, it has been determined that in case of approximate method the resonance frequencies cover with those which have been determined with the exact method. However the values of the characteristic in other areas were different. The main aim of this paper is to compare the transients of characteristics of mechanical subsystem of the transverse vibrating discrete - continuous mechatronic system, obtained by the exact and the approximate Galerkin method and to answer the question - if the method can be used to nominate the characteristics of mechatronic systems. The main subject of deliberation was to determine the flexibility of the mechanical system with constant cross-section using the exact and the Galerkin method. The problems presented in this paper, that means the analysis of subsystem of mechatronic and mechanical complex systems, is however the introduction to the synthesis of transverse vibrating mechatronic systems with assumed frequency spectrum.
5
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Apatite Wollastonite-Reinforced Hydroxyapatite Biocomposites

100%
Çalışkan F.
Acta Physica Polonica A
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2016
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vol. 129
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issue 4
665-668
EN
The paper is focused on the reinforcement of hydroxyapatite (HA) by apatite wollastonite (AW) because of its aptitude for combining biocompability with mechanical properties superior to those of the bone. HA powders were produced by thermal extraction technique involving calcination from natural source. HA-AW_{P} biocomposites containing from 0 to 20 wt.% of AW in particulate form were prepared starting with wet ball milling during 24 h, followed by powder metallurgical processes using HA powders calcined at 800°C, followed by compaction by cold pressing and by cold isostatical pressing at 250 MPa and subsequent sintering at 1100-1300°C. The phases and compositions in the resulting products were identified by XRD and XRF. Reinforcement particle distribution were investigated on polished surfaces of the sintered samples by SEM analysis and by optical microscopy. Mechanical properties of the sintered samples was evaluated via Micro Vickers hardness testing.
6
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Optimization of Cutting Parameters, Condition and Geometry in Turning AISI 316L Stainless Steel Using the Grey-Based Taguchi Method

100%
Basmaci G., Ay M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
354-358
EN
In this study, experimental optimization of cutting forces, surface roughness and the hardness of material after turning of AISI 316L stainless steel, using conventional and wiper insert cutting tools under dry, CO₂ and MQL cutting conditions, is presented. The influences of feed rate, cutting depth, and cooling system on surface roughness, cutting force and material hardness were examined. In order to optimize the turning process, Grey relational analysis optimization method was used. The optimal machinability parameters of AISI 316L stainless steel with coated carbide insert were successfully determined.
7
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Optimisation of Machining Parameters in Turning AISI 304L Stainless Steel by the Grey-Based Taguchi Method

100%
Ay M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
349-353
EN
In this study, an experimental optimization of cutting forces and surface roughness in turning of AISI 304L stainless steel using wiper and conventional insert cutting tools with dry cutting conditions are presented. The influences of feed rate, depth of cut, and corner radius on surface roughness, cutting force and surface hardness are examined. In order to optimize the turning process, Grey relational analysis optimization method is used. The optimal machinability conditions of AISI 304L stainless steel with coated carbide insert are successfully determined in this study.
8
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Investigation on Effects of Schiff Base Complex to Hydroxyapatite Bioceramics

100%
Çalışkan F., Tuna M., Akça S.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
1393-1396
EN
The aim of this study was to evaluate the effects of Schiff base metal complex on the bio-compatible hydroxyapatite (HAp) ceramics. The reason for that was to produce, as the final product, the HAp in powder form, with extraordinary features like analgesic, antibacterial properties. This effect was provided by doping HAp powder with some Schiff base complexes during the powder extraction process. Schiff base complex used in the study was synthesized by condensation of primary amines with carbonyl compounds. The chemical structures of the synthesized compounds were confirmed by means of infrared (IR) spectroscopy and elemental analysis. Characterizations of the extracted HAp powders were carried out by using scanning electron microscopy for surface analysis and EDS analysis, X-ray diffraction for phase determination and grain size distribution. The bactericide effects of Zn SAE-added pure HAp were tested on E.Coli bacteria for the content range of 0-7 wt.% of Zn-SAE. Consequently, bacterial activity of the calcium phosphate resulting powders was evolved by adding the Zn SAE Schiff base complex.
9
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Comparative Study of Phases Forming in Niobium-Antimony Oxides System upon High Temperature Treatment and High-Energy Ball Milling

100%
Dulian P., Piz M., Filipek E., Wieczorek-Ciurowa K.
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vol. 126
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issue 4
938-942
EN
The compound SbNbO_4 that is formed in a ternary system of Nb-Sb-O has been obtained for the first time by high-energy ball milling of the equimolar mixture of oxides Sb_2O_3/Nb_2O_5in argon atmosphere. This compound was characterised by X-ray diffraction, differential thermal analysis- thermal gravimetry, infrared, and scanning electron microscopy methods and its properties were compared with those of SbNbO_4 also obtained as a result of high-temperature reaction between the same oxides and also in argon atmosphere. As shown by differential thermal analysis results, irrespective of the method of synthesis, SbNbO_4 is stable in argon atmosphere up to ≈ 1125°C and in air up to ≈ 800°C. The compound can be applied as a photocatalyst in the reaction of producing hydrogen from water.
10
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Fabrication of Functional Graded Al2124 Composite Reinforced with Al₂O₃ Particles

100%
Çalışkan F., Cömert S., Kocaman E.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
437-439
EN
The composite materials formed by powder metallurgy are mostly used in industry due to their excellent properties such as low density, high strength, and hardness. The aim of this study is to produce functional graded Al material reinforced with macro-sized Al₂O₃. To fabricate the aluminum matrix composite, commercial Al 2124 aluminum alloy powder (from Gürel Makina), which is used in aerospace and defense industries, was chosen as a matrix material. Powder metallurgy was used to produce the functional graded material because it allows an easy incorporation of reinforcement phase into the matrix. The sintered samples were characterized using optical microscopy, SEM, and X-Ray diffraction analysis. The results show that functional graded material structure and the transition interlayers were achieved by the presented process.
11
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Joint Strength Optimization of Bi-Adhesively Bonded Composite-Aluminum Sandwich Structure

100%
Uysal M.
Acta Physica Polonica A
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2016
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vol. 129
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issue 4
445-447
EN
Adhesively bonded joint strength optimization can be obtained through the modification of the overlap length and bi-adhesively bonded technique. In this technique, the joints have two different types of adhesive in the overlap length. In the present paper, the effects of bi-adhesively bondline on the shear stress, peeling stress and von-Mises stress of tongue and groove joints were investigated by using finite element analysis. The joint models were consisted of thick woven E-glass/vinyl ester laminate composite groove geometry together with aluminum 5083 tongue geometry. Finite element analyses were performed for three different tongue lengths (75, 150, 225 mm). The distribution of shear and peeling stresses were investigated on adhesively bonded tongue and groove joints subjected to longitudinal tensile loads. The results indicated that the joint strength can be improved by selecting appropriate design parameter values with bi-adhesive bonded technique.
12
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Investigation of Surface Roughness and Chip Forms in Milling of Stainless Steel by MQL Method

100%
Uysal A., Demiren F., Altan E.
Acta Physica Polonica A
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2016
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vol. 129
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issue 4
439-441
EN
Stainless steel materials have been used in many fields such as automotive, food, medical, chemistry etc. by applying machining operations although they are categorized under a group of materials whose machinability is difficult due to high strength, low thermal conductivity and work hardening tendency during machining. It is possible that these materials can be machined by using various cutting fluids, but cutting fluids have disadvantages such as being harmful to the environment and health. In this study, it is intended that the minimum quantity lubrication method is applied by using commercial vegetarian cutting fluid and uncoated and TiN coated WC cutting tools during milling of AISI 304 (austenitic stainless steel) and AISI 420 (martensitic stainless steel) materials and the sustainable machining is realized. Milling operations will be repeated even by applying the dry machining for the purpose of being able to compare the results obtained from minimum quantity lubrication method. The workpiece surface roughness and chip forms were investigated.
13
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Magnetic Force Microscopy of the Ethmoid Bones of Migratory and Non-Migratory Fishes

100%
Gorobets S., Gorobets O., Bulaievska M., Sharau I.
Acta Physica Polonica A
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2018
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vol. 133
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issue 3
734-737
EN
For a long time it was believed that the biogenic magnetic nanoparticles (BMNs) in the ethmoid bones of fishes and birds are associated with navigation in the geomagnetic field. However, it was proven that BMNs don't affect the ability of migratory birds to orient in the Earth's magnetic field. It is relevant to check the presence of BMNs in organs of migratory and non-migratory fishes. The presence of BMNs was investigated in the samples of ethmoid bones of atlantic salmon, northern pike and silver carp by the method of magnetic force microscopy. As a result, the biological material of ethmoid bones of migratory and non-migratory fishes contain both separate BMNs and their chains, so BMNs in the ethmoid bone of fishes are not related to their ability to migrate in the geomagnetic field.
14
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Effect of Severe Plastic Deformation on Wear Properties of Aluminum Matrix Composites

100%
Karademir I., Unal O., Ates S., Gokce H., Gok M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
487-489
EN
The influence of severe plastic deformation on wear properties of Al-5wt.%Grp and Al-5wt.%B₄Cp reinforced aluminum matrix composites was studied. Al matrix composites were produced by solid state processing via powder metallurgy route that provides good incorporation and distribution of the reinforcement particles in the matrix. Wear tests were performed by dry sliding using a pin on disk wear tester. Scanning electron microscope was used to examine worn surfaces to study the wear mechanism. Severely deformed specimens exhibited better wear resistance due to the increase of surface hardness of both Al-5wt.%Grp and Al-5wt.%B₄Cp composites. Al-B₄Cp reinforced composite has higher hardness value through the excellent hardness of B₄C particulates. Al-Grp reinforced composites exhibited better wear resistance due to the solid lubricant effect of Gr particulates.
15
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Effect of Copper Addition to Aluminium Alloys on Surface Roughness in Terms of Turning Operation

100%
Özen F., Fıçıcı F., Dündar M., Çolak M.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
467-469
EN
Aluminium alloys have found usage in numerous industries due to some superior properties, such as high strength-to-weight ratios and high oxidation resistance. Aluminum alloys can be strengthened by some techniques. One of them, the most practical one, is precipitation hardening in aluminum alloys. By adding Cu, aluminum gains strength and hardness. In this work the machinability of unalloyed aluminum and aluminum alloyed with 4% and 8% of Cu have been investigated. Machinability assessment was executed in terms of surface roughness during turning operation. Specimens were manufactured by sand casting method, which is a commonly utilized casting operation. In machinability experiments, three different cutting tool materials were employed. Three different cutting speeds and three different feed rates have been used. Effect of these feeds, speeds and cutting tool materials on surface roughness has been studied. In addition, effect of Cu addition to aluminum alloys on surface roughness has been examined.
16
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Synthesis of the in-Situ Si₃N₄-SiC Composite Nano Powders by Carbothermal Reduction

100%
Çalışkan F., Kocaman E., Cömert S.
Acta Physica Polonica A
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2017
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vol. 131
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issue 3
601-604
EN
Si₃N₄-SiC micro-nano composite powder has been studied by a group of authors during the last decade. Previous works have shown that SiC-Si₃N₄ ceramics exhibits good mechanical properties and high corrosion resistance at elevated temperatures. In this study, we have tried a new approach to obtaining SiC-Si₃N₄ ceramic composite powder by changing the conditions in the carbothermal reduction process. Starting powders were quartz mineral, received from Ege-Sil Co., as silicon-source and, carbon, as silica-reducing and carburizing agent. These powders were ground in the ring mill, separately and together. Carbothermal reduction-nitridation/carburization reactions were carried out in a tube furnace at >1400°C for 4 hours under N₂ and Ar gas, used as nitriding and shielding atmosphere. The synthesized powders were characterized by X-ray diffraction, SEM, and EDS. Results have shown that production of Si₃N₄-SiC micro-nano composite powder was achieved in the modified nitrogen and argon atmosphere above 1400°C. Determination of the Si₃N₄/SiC ratio was possible with sensitive control of the system conditions.
17
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In Situ Solution Process for Fabricating Thermally and Mechanically Stable Highly Conductive ZnO-CNT Fiber Composites

100%
Hossain M., Son S., Hahn J.
Acta Physica Polonica A
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2017
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vol. 131
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issue 1
124-132
EN
A simple in situ solution process was developed to produce a mechanically and thermally stable ZnO-carbon nanotube fiber composite. ZnO nanoparticles were homogeneously deposited onto the surfaces of and interstices within CNT fibers (between individual CNTs). X-ray photoelectron spectroscopy and Raman analysis revealed that ZnO nanoparticles contained oxygen vacancy defects and CNT fibers included oxygen containing functional group that strongly interacted with Zn. The strong interaction enhanced the mechanical properties of the composite fibers. The Young modulus (20 GPa) and tensile strength (118 MPa) were enhanced compared to the corresponding values of the pristine CNT fibers. The thermal stability was high up to 880°C and light absorption was enhanced across the UV to near IR region in a ZnO-CNT fiber composite. The electrical conductivity of the composite was high up to 954 S/cm despite semiconductor deposition.
18
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The Usage of Perlitic Pumice from İzmir-Menderes (Turkey) in the Production of Low-Strength Lightweight Concrete

63%
Ceylan H., Saraç S.
Acta Physica Polonica A
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2017
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vol. 132
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issue 3
667-669
EN
Lightweight aggregates, used to produce cavity blocks in the construction sector, vary according to their technical properties and thus, technical analyses should be performed on lightweight aggregate specimens. Lightweight aggregates, like pumice, are widely employed for the production of construction elements, used as light masonry units. In literature there are studies related to applications of various lightweight aggregates, such as volcanic slag, ignimbrite and expanded clay, in addition to pumice, to produce porous cavity blocks. This study investigates the usability of perlitic pumice formations, present around Menderes, İzmir (Turkey), as lightweight aggregate. Many experiments were conducted to investigate this possibility and to determine the optimum mixing ratios of aggregate. Based on the results, for 10% of cement by volume, the optimum aggregate mixing ratio was 40% 0-4 mm and 60% 4-8 mm.
19
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Investigation on Water Retention Properties of Boric Acid Doped Textile Surfaces

63%
Akarslan F., Altinay Ö.
Acta Physica Polonica A
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2015
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vol. 128
|
issue 2B
B-405-B-406
EN
During the summer periods, the excellent absorbency and high water retention capacity of textile materials is important to eliminate the disturbing effect of perspiration. In this study, water retention properties of boric acid-doped textile surfaces has been investigated. For this purposes different proportions of boric acid were applied to 100% cotton fabric by means of impregnation method. Then, water retention was tested according to DIN 53923 standard, as a percentage of the water retention rate. The results were analyzed.
20
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Effect of Microstructure on the Corrosion Resistance of the AE42 Magnesium Alloy Processed by Rotary Swaging

63%
Minárik P., Zemková M., Král R., Mhaede M., Wagner L., Hadzima B.
Acta Physica Polonica A
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2015
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vol. 128
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issue 4
805-807
EN
Microstructure and corrosion resistance of the AE42 commercial alloy processed by extrusion and rotary swaging were investigated. Microstructure characterization showed an increasing volume fraction of the refined grains with increasing stage of swaging processing. However, their presence was limited solely to the peripheral ring of ≈1 mm in all studied conditions of swaged material. Corrosion resistance investigation showed continuous decrease of polarization resistance that was attributed to the grain refinement and insufficient homogenization of the alloying elements during the swaging process.
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