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Tytuł:
Impact of orthodontic adhesive magnets on the mechanical properties and degree of conversion of a photopolymerized orthodontic adhesive
Wpływ ortodontycznych magnesów samoprzylepnych na właściwości mechaniczne i stopień konwersji fotopolimeryzowanego kleju ortodontycznego
Autorzy:
Al-Hayali, Saud Khalil
Abed, Mazin Ahmed
Al Qassar, Sarmad Salih
Powiązania:
https://bibliotekanauki.pl/articles/41152047.pdf
Data publikacji:
2023
Wydawca:
Wydawnictwo SIGMA-NOT
Tematy:
degree of conversion
magnetic field
polymer
orthodontic adhesive
microhardness
compression strength
stopień konwersji
pole magnetyczne
polimer
klej ortodontyczny
mikrotwardość
wytrzymałość na ściskanie
Opis:
The purpose of this study was to calculate the effects of magnetic field (MF) on the degree of conversion (DC%) and mechanical properties of a photopolymerized orthodontic adhesive. In this investigation, Vega Ortho UV orthodontic adhesive was employed. The applied magnetic field had varying intensities (fixed at 0.01 T, 0.03 T, 0.05 T, 0.1 T, 0.15 T, and 0.2 T and a duration of 5 minutes) and a fixed frequency of 50 Hz. Vickers microhardness and DC% were investigated utilizing the specimens, which were created using circular molds and prepared for compression strength (CS) testing in accordance with ISO 4049. To evaluate DC% before and after MF exposure, Fourier-transform infrared spectroscopy (FTIR/ ATR) was performed. A microhardness tester was used to quantify the samples’ initial VHN while subjecting them to a 500 g load for 15 seconds. After that, properties were evaluated. With the aid of scanning electron microscopy (SEM), the surfaces were evaluated. The one-way analysis of difference and Tukey significant difference tests were used to evaluate the data. Analyses of statistical data showed that DC% tends to rise up to 0.05 T. When compared to the control, VHN and compression strength were considerably decreased after 0.03 T MF (p ≤ 0.05). However, there was a significant difference between the VHN and CS as their values increased with increasing magnetic field intensity. The surfaces of the Vega Ortho were deteriorated, as shown by SEM scans. It was found that the effect of the magnetic field caused changes in the physical and chemical properties.
Celem badania było określenie wpływu pola magnetycznego (MF) na stopień konwersji (DC%) i właściwości mechaniczne fotopolimeryzowanego kleju ortodontycznego. W badaniu zastosowano klej ortodontyczny Vega Ortho UV. Zastosowane pole magnetyczne miało różne natężenia (0,01 T, 0,03 T, 0,05 T, 0,1 T, 0,15 T i 0,2 T przez 5 minut) i stałą częstotliwość 50 Hz. Mikrotwardość Vickersa i DC% ustalono z wykorzystaniem próbek, które zostały wykonane przy użyciu okrągłych form i przygotowane do badania wytrzymałości na ściskanie (CS) zgodnie z normą ISO 4049. Do oceny DC% przed ekspozycją na działanie pola magnetycznego i po niej wykorzystano spektroskopię w podczerwieni z transformacją Fouriera (FTIR/ATR). Do ilościowego określenia początkowej wartości VHN próbek użyto mikrotwardościomierza, poddając je obciążeniu 500 g przez 15 sekund. Następnie dokonano oceny właściwości. Ocenę powierzchni przeprowadzono za pomocą skaningowej mikroskopii elektronowej (SEM). Dane poddano jednokierunkowej analizie różnic i testowi istotnej różnicy Tukeya. Analizy danych statystycznych wykazały, że DC% ma tendencję do wzrostu do poziomu 0,05 T. W porównaniu z próbką kontrolną wartości VHN i wytrzymałości na ściskanie uległy znacznemu zmniejszeniu po oddziaływaniu 0,03 T MF (p ≤ 0,05). Istniała jednak znacząca różnica między VHN i CS, ponieważ ich wartości rosły wraz ze wzrostem natężenia pola magnetycznego. Powierzchnie Vega Ortho uległy degradacji, jak wykazały skany SEM. Stwierdzono, że wpływ pola magnetycznego spowodował zmiany właściwości fizykochemicznych.
Źródło:
Ochrona przed Korozją; 2023, 10; 329-334
0473-7733
2449-9501
Pojawia się w:
Ochrona przed Korozją
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of heat treatment on microhardness of electroless Ni-YSZ cermet coating
Autorzy:
Bahiyah Baba, N.
Ghazali, A. S.
Abdul Rahman, A. H.
Sharif, S.
Powiązania:
https://bibliotekanauki.pl/articles/2201036.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
Ni-YSZ
cermet
coating
microhardness
heating temperature
heating time
electroless nickel
powłoka
mikrotwardość
temperatura nagrzewania
czas nagrzewania
bezprądowe powlekanie niklem
Opis:
Purpose: The paper discussed the effect of heat treatment on electroless nickel-yttria-stabilised zirconia (Ni-YSZ) cermet coating. Ni-YSZ cermet coating has potential applications such as cutting tools, thermal barriers, solid oxide fuel anode, and various others. The compatibility of ceramic YSZ and metallic nickel in terms of the mechanical properties such as hardness by varying the heating temperature, time and ceramic particle size is highlighted. Design/methodology/approach: Ni-YSZ cermet coating was deposited onto a highspeed steel substrate using the electroless nickel co-deposition method. The temperature and time were varied in a range of 300-400°C and 1-2 hours, respectively. The microhardness measurements were carried out using a Vickers microhardness tester (Shimadzu) according to ISO 6507-4. The surface characterisation of the cermet coating was carried out using JOEL Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray (EDX) JSM 7800F. The crystallographic structure of materials was analysed by X-ray diffraction (XRD) Bruker D8 Advance instrument. Findings: It was found that the microhardness of Ni-YSZ cermet coating with the ratio of 70:30, respectively, is directly proportional to the heating temperature and time. Heating the Ni-YSZ cermet coating at 300°C from room temperature (rtp) to 1 hour shows a 12% microhardness increment, while from 1 to 2 hours gives a 19% increment. Compared to heating at 350°C and 400°C, the increment is more significant at 33% and 49% for rtp to 1 hour and 8% and 16% for 1 to 2 hours, respectively. In addition, the effect of varying YSZ particle size in the Ni-YSZ cermet gave response differently for heating temperature and heating time. Research limitations/implications: The paper is only limited to the discussion of the heat treatment effect on Ni-YSZ cermet coating hardness property. The tribological effect will be in future work. Practical implications: The microhardness data may vary due to the Vickers microhardness force applied and the amount of ceramic particle incorporation and phosphorus content in the nickel matrix. Originality/value: The value of this work is the compatibility of the ceramic YSZ and metallic nickel matrix in terms of mechanical properties, such as hardness, upon heat treatment.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2022, 113, 1; 5--12
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of heat treatment on the properties of explosively welded Cu-Al joint
Wpływ obróbki cieplnej na właściwości złączy Cu-Al zgrzewanych wybuchowo
Autorzy:
Lokaj, Jan
Sahul, Miroslav
Sahul, Martin
Čaplovič, Ľubomír
Powiązania:
https://bibliotekanauki.pl/articles/27787764.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
explosive welding
detonation velocity
copper
aluminium alloy
intermetallic compounds
EDS analysis
microhardness
zgrzewanie wybuchowe
prędkość detonacji
miedź
stop aluminium
związki międzymetaliczne
analiza EDS
mikrotwardość
Opis:
Explosive welding of copper C10200 to aluminium alloy AW 5083 was performed. C10200 was proposed as a flyer plate due to its suitable plastic properties. A parallel layout of welded metals was selected to attain a more stable welding process. Welding parameters and conditions were determined. The surfaces of both materials were mechanically machined and degreased prior to welding which was performed using Semtex S30. The bimetals were characterized by a regular wavy interface. The aim of the research was to establish the influence of heat treatment on both the structure and microhardness at the interface of the explosively welded bimetal Al-Cu. Heat treatment was performed at 250, 300 and 350 °C over 2, 3 and 4 h. After heat treatment, an increase in Inter Metallic Compounds (IMC) was observed, proportional to the increasing temperature. An analysis of chemical composition carried out by EPMA (Electron Probe Micro Analysis) confirmed the presence of Inter Metallic Phases (IMP) such as θ (Al2Cu), η2 (Al2Cu), ξ2 (Al3Cu4), δ (Al2Cu3), γ1 (A14Cu9). The microhardness decreased after the heat treatment in the bimetal but significantly increased at the interface as a consequence of IMC formation.
Wykonano zgrzewanie wybuchowe stopu aluminium miedź C10200 i AW 5083. C10200 został zaproponowany jako płyta napędzana ze względu na jego odpowiednie właściwości plastyczne. Wybrano równoległy układ zgrzewanych metali, aby uzyskać bardziej stabilny proces łączenia. Określono parametry i warunki łączenia. Powierzchnie obu materiałów zostały poddane obróbce mechanicznej i odtłuszczeniu przed zgrzewaniem wykonanym przy użyciu Semtex S30. Bimetale charakteryzowały się regularną falistą powierzchnią styku. Celem badań było określenie wpływu obróbki cieplnej zarówno na strukturę, jak i mikrotwardość na granicy faz bimetalu Al-Cu zgrzewanego wybuchowo. Obróbkę cieplną przeprowadzono w 250, 300 i 350 °C przez 2, 3 i 4 godziny. Po obróbce cieplnej zaobserwowano wzrost związków międzymetalicznych (IMC), który był proporcjonalny do wzrostu temperatury. Analiza składu chemicznego przeprowadzona przez EPMA (Electron Probe Micro Analysis) potwierdziła obecność IMP takich jak θ (Al2Cu), η2 (AlCu), ξ2 (Al3Cu4), δ (Al2Cu3), γ1 (Al4Cu9). Mikrotwardość zmniejszyła się po obróbce cieplnej w bimetalu, ale znacznie wzrosła na granicy faz w wyniku tworzenia IMC.
Źródło:
Materiały Wysokoenergetyczne; 2022, 14; 4--13
2083-0165
Pojawia się w:
Materiały Wysokoenergetyczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parametric optimisation of microhardness on heat-treated electroless Ni-YSZ cermet coating
Autorzy:
Bahiyah Baba, N.
Ghazali, A. S.
Abdul Rahman, A. H.
Sharif, S
Powiązania:
https://bibliotekanauki.pl/articles/2172165.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
full factorial
electroless
Ni-YSZ
cermet
coating
microhardness
treating temperature
treating time
silnia
bezprądowy
powłoka
mikrotwardość
temperatura obróbki
czas obróbki
Opis:
Purpose The paper discusses the parametric optimisation of the electroless Ni-YSZ cermet coating microhardness upon heat treatment. Heat treatment is a process to increase the mechanical properties of the electroless nickel coating and it can be enhanced by manipulating its parameters. Parametric optimisation is conducted by the design of experiment full factorial 3x3 with 27 runs. Treating temperature, treating time and ceramic particle size parameters at 3-level are evaluated using statistical tool ANOVA in Minitab20. Design/methodology/approach Ni-YSZ cermet coating is deposited onto a high-speed steel substrate using the electroless nickel co-deposition method. The temperature and time were varied in a range of 300-400oC and 0-2 hours respectively. The microhardness measurements were carried out using a Vickers microhardness tester (Shimadzu) according to ISO 6507-4. The surface characterisation was analysed using Cambridge Stereoscan 90 Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray Analysis (EDXA). Findings The optimum condition in obtaining high microhardness on Ni-YSZ cermet coating is evaluated by statistical tool ANOVA in Minitab20 software. It is found that the most significant parameter for high microhardness is at the treating temperature of 400oC followed by treating time at 2 hours using nano-sized YSZ particles. The ceramic particle size is found not a significant parameter in obtaining a high microhardness, however it has effect on interaction between treating temperature and treating time. Research limitations/implications The paper only limits to the optimisation condition of microhardness on Ni-YSZ cermet coating hardness property by varying heat treatment parameters. Practical implications The optimisation condition obtained might only applicable to the electroless Ni-YSZ cermet coating with similar electroless nickel solution and treatments. Originality/value The value of this work is the heat treatment parametric optimisation to obtain high microhardness on electroless Ni-YSZ cermet coating by using the design of experiment 3-level full factorial.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2022, 112, 1; 33--41
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of workpiece speed on microhardness and residual stresses in vacuum-carburised 20MnCr5 steel using the single-piece flow method
Autorzy:
Sawicki, J.
Januszewicz, B.
Sikora, M.
Witkowski, B.
Powiązania:
https://bibliotekanauki.pl/articles/24200559.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
surface grinding
microhardness
residual stress
vacuum carburising
single-piece flow
szlifowanie powierzchni
mikrotwardość
naprężenie szczątkowe
nawęglanie próżniowe
przepływ jednoczęściowy
Opis:
Purpose: To determine the impact of selected conditions of abrasive treatment on the value and distribution of microhardness and residual stresses in layers carburised by a continuous single-piece flow method. Design/methodology/approach: Reference pieces were low pressure carburised at 920°C and then heat-treated in a 4D Quench heat treatment chamber at a pressure of 7 bar and tempered at 190ºC for 3 hours. In the next stage, samples were ground at various vw piece speeds, introducing grinding fluid into the cutting zone using the WET spraying method or using the MQL method at a minimum flow rate. The distribution of microhardness and residual stresses generated in the technological outer layer of the pieces following heat and chemical treatment and the grinding process was measured. Findings: Results of the tests indicated that the vw piece speed and method used to supply cooling and lubricating fluid to the grinding zone had an impact on selected parameters of the technological outer layer of flat samples made of 20MnCr5 steel. The process of grinding using an electrocorundum grinding wheel results in a deterioration of residual stresses in the material. For each of the three analysed vw piece speeds, reduced changes in material microhardness prior to cutting occur in the outer layer of samples ground using GF supplied at a minimum flow rate using the MQL method. Research limitations/implications: Environmental considerations and having to conform to increasingly stringent regulations related to environmental protection and employee safety motivate researchers and businesses to entirely eliminate or reduce the use of grinding fluids in the grinding process and, therefore, to optimise grinding technology. Practical implications: Modern manufacturing industry requires the grinding process, which follows heat and chemical treatment, to be performed with the highest possible efficiency. However, retaining high parameters of the technological outer layer in comparison to the sample material following vacuum carburisation (before grinding) is extremely difficult. An optimised configuration of parameters of the grinding process and method of supplying grinding fluids enables meeting the current and future high expectations of the industry in this regard. Originality/value: The tests have enabled us to determine the impact of the applied vw workpiece speed and method of supplying grinding fluid on microhardness and residual stresses. Generally speaking, grinding with an electrocorundum grinding wheel results in a deterioration of residual stresses. For both methods of supplying GF (WET and MQL), the distribution of microhardness in the material of the samples ground with the highest workpiece speed (18.0 m/min) indicated no significant differences with regard to the distribution of microhardness in the material of the samples following heat and chemical treatment.
Źródło:
Archives of Materials Science and Engineering; 2022, 115, 2; 66--75
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of yttria content and sintering temperature on the microstructure and tendency to brittle fracture of yttria-stabilized zirconia
Autorzy:
Kulyk, V.V.
Duriagina, Z.A.
Vasyliv, B.D.
Vavrukh, V.I.
Lyutyy, P.Ya.
Kovbasiuk, T.M.
Holovchuk, M.Ya.
Powiązania:
https://bibliotekanauki.pl/articles/2175775.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
YSZ ceramics
microhardness
fracture toughness
microstructure
fracture micromechanism
ceramika YSZ
mikrotwardość
odporność na pękanie
mikrostruktura
mikromechanizm pękania
Opis:
Purpose: The purpose of this work is to evaluate the propensity to brittle fracture of YSZ ceramics stabilized by the various amount of yttria, based on a study of changes in the microstructure, phase composition, and fracture micromechanisms. Design/methodology/approach: The series of 3YSZ, 4YSZ, and 5YSZ ceramic specimens were sintered in an argon atmosphere. Three sintering temperatures were used for each series: 1450°C, 1500°C, and 1550°C. Microhardness measurements were performed on a NOVOTEST TC-MKB1 microhardness tester. The configuration of the imprints and cracks formed was studied on an optical microscope Neophot-21. The fracture toughness of the material was estimated using both the Vickers indentation method and a single-edge notch beam (SENB) test performed under three-point bending at 20°C in air. The microstructure and morphology of the fracture surface of the specimens were studied using a scanning electron microscope Carl Zeiss EVO-40XVP. The chemical composition was determined using an INCA ENERGY 350 spectrometer. Findings: Peculiarities of changes in the microstructure, the morphology of specimens fracture surface, and mechanical characteristics of YSZ ceramic materials of different chemical and phase compositions sintered in a temperature range of 1450°C to 1550°C are found. Research limitations/implications: To study the actual behaviour of YSZ ceramic materials under operating conditions, it is necessary to evaluate their Young’s moduli, strength, microhardness, and fracture toughness in an operating environment of the corresponding parameters (temperature, pressure, etc.).Practical implications: Based on the developed approach to estimating the propensity to brittle fracture of the formed YSZ ceramic microstructure, it is possible to obtain YSZ ceramic material that will provide the necessary physical and mechanical properties of a wide variety of precision ceramic products. Originality/value: An approach to estimating the propensity to brittle fracture of YSZ ceramics stabilized by the various amount of yttria is proposed based on two methods of evaluating crack growth resistance of materials, namely, the Vickers indentation method and SENB method.
Źródło:
Archives of Materials Science and Engineering; 2021, 109, 2; 65--79
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forecasting process parameters on weld nugget hardness of filler added friction stir welded dissimilar aluminium alloys 5052 And 6082 joints
Autorzy:
Sasikumar, A.
Gopi, S.
Mohan, Dhanesh G.
Powiązania:
https://bibliotekanauki.pl/articles/2052239.pdf
Data publikacji:
2021
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
friction stir welding
center distance between the holes
filler ratio
microhardness
response surface methodology
zgrzewanie tarciowe z przemieszaniem
współczynnik wypełnienia
mikrotwardość
metodologia powierzchni odpowiedzi
Opis:
This article deals with the optimization of friction stir welding process parameters with filler ratios on dissimilar Aluminium alloy groups. For this purpose, 6 series Aluminium alloy 6082 and 5 series Aluminium alloy 5052 were taken. Microhardness property was conducted under various rotational speeds, welding speed, plunge depth, Center distance between the holes and filler mixing ratio. The Central Composite Design (CCD), the most commonly used Response Surface Methodology (RSM), is considered to develop the prediction equation. A validation analysis is carried out, and the results were compared with the relative impact of input parameters on weld nugget microhardness. It is observed that the increase in welding speed with plunge depth and filler ratio result in the increase of weld nugget microhardness up to a maximum value. The maximum weld nugget hardness of fabricated joint was obtained with the welding process parameters combination of 1000 rpm rotational speed, 125 mm/min welding speed, 0.15 mm plunge depth, 2 mm centre distance between the holes, and filler ratio of 95% Mg and 5% Cr.
Źródło:
Journal of Mechanical and Energy Engineering; 2021, 5, 2; 103-112
2544-0780
2544-1671
Pojawia się w:
Journal of Mechanical and Energy Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hardness investigation of conventional, bulk fill and flowable dental composites
Autorzy:
Georgiev, G.
Dikova, T.
Powiązania:
https://bibliotekanauki.pl/articles/2055754.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
resin-based composites
micro-hardness
light intensity
irradiation time
layer thickness
kompozyty żywiczne
mikrotwardość
natężenie oświetlenia
czas nasłonecznienia
grubość warstwy
Opis:
Purpose: of the present paper is to investigate the micro-hardness of three types of resin-based composites – conventional, bulk fill and flowable. Design/methodology/approach: Cylindrical specimens with a diameter of 5 mm and thicknesses of 2, 3 and 4 mm were made from each composite. They were light cured for 20, 40 and 60 s with light intensity of 600, 1000 or 1500 mW/cm2. The Vickers micro-hardness was measured on the top and bottom surface of the specimens. Findings: The highest micro-hardness was measured in bulk fill composite, followed by conventional and the lowest was measured in the flowable one. Increasing the light intensity leads to increase of the micro-hardness on both surfaces of the three composites. The increase of the irradiation time results in increase of the micro-hardness mainly on the bottom surface of the composites. The change of the layer thickness influences the conventional and the flowable composites and almost does not affect the hardness of the bulk fill composite. Research limitations/implications: The limitations of this study concerns to the values of the light intensity, which are defined by the light curing unit (LCU) used. There are many LCUs on the market; consequently, constant investigations of dental composites micro-hardness are needed. Practical implications: The investigation of the micro-hardness of the three types of composites in different modes would be very helpful for clinicians to obtain successful polymerization of composite restorations in their everyday practice. Originality/value: The micro-hardness of three types resin-based dental composites – conventional, bulk fill and flowable is investigated and compared in varying of three mode parameters – light intensity, curing time and layer thickness.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2021, 109, 2; 68--77
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Impact of Biomateriał and the Technology of Prosthetic Crowns Manufacturing on The Connection with Veneering Ceramics
Analiza wpływu biomateriału i technologii wytworzenia koron protetycznych na łączenie z ceramiką licującą
Autorzy:
Ryniewicz, Anna M.
Ryniewicz, Andrzej
Bojko, Łukasz
Ryniewicz, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/1857795.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
layered structures
CAD/CAM milling
SLM
concentrated contact
microhardness
struktury warstwowe
frezowanie CAD/CAM
styk skoncentrowany
mikrotwardość
Opis:
The aim of the study is to identify the endurance parameters of prosthetic crowns veneered with dedicated ceramics on metal, glass-ceramic, and ceramic frameworks. Metal frameworks were made using CAD/CAM milling technology and SLM technology, while the glass-ceramic and ceramic frameworks were produced using only the CAD/CAM milling technology. The research materials are samples replicating the layered structures of prosthetic crowns. The veneering procedure must ensure the adhesion of the ceramics to the loadbearing framework. The tests modelling the conditions of concentrated loads during chewing were carried out using the Instron 3345 testing machine. Determination of microhardness in cross-sections through layered structures of crowns was performed using the HMV Micro Hardness Tester. The comparison of force loading the indenter as a function of penetration depth indicates that the value of the maximum depth depends on the configuration of microhardness of the framework and dentine. The zirconium ceramics ZrO2 (3Y-TZP) – veneered with Elephant Sakura silica ceramics – should be indicated as the most advantageous material composition.
Celem pracy jest identyfikacja parametrów wytrzymałościowych koron protetycznych licowanych dedykowanymi ceramikami na podbudowach metalowych, szklanoceramicznych i ceramicznych. Podbudowy metalowe zostały wytworzone w technologii frezowania CAD/CAM i w technologii SLM, a podbudowy szklanoceramiczne i ceramiczne w technologii frezowania CAD/CAM. Materiałem badań są próbki replikujące warstwowe struktury koron protetycznych. W wyniku procedury licowania musi być zapewniona adhezjaceramiki do podbudowy nośnej. Badania modelujące warunki skoncentrowanych obciążeń podczas żucia wykonano na maszynie wytrzymałościowej Instron 3345. Wyznaczenie mikrotwardości w przekrojach przez warstwowe struktury koron zrealizowano na maszynie HMV Micro Hardness Tester. Zestawienie siły obciążającej wgłębnik w funkcji głębokości penetracji wskazuje, że wartość maksymalnego zagłębienia, zależy od konfiguracji mikrotwardości podbudowy i mikrotwardości dentyny. Jako najkorzystniejszą kompozycję materiałową należałoby wskazać ceramikę cyrkonową ZrO2 (3Y – TZP) – licowaną ceramiką krzemionkową Elephant Sakura.
Źródło:
Tribologia; 2020, 293, 5; 17-25
0208-7774
Pojawia się w:
Tribologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure and electrochemical properties of the vanadium alloys after low-temperature nitrogen plasma treatment
Autorzy:
Duriagina, Z. A.
Ryzhak, D. D.
Kulyk, V. V.
Tepla, T. L.
Lemishka, I. A.
Bohun, L. I .
Powiązania:
https://bibliotekanauki.pl/articles/1818517.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
vanadium alloy
surface layers
microhardness
corrosion
stop wanadu
warstwy powierzchniowe
mikrotwardość
korozja
Opis:
Purpose: The proposed research aims to determine the expediency of surface treatment of vanadium alloys of V-Cr and V-Ti systems due to irradiation of their surfaces with low- temperature nitrogen plasma using plasma torch NO-01. Design/methodology/approach: The investigation of microstructure and X-ray fluorescence analysis (XRF) of the samples were performed using an electron microscope TESCAN Vega3. The microhardness (Vickers hardness) of the samples was measured before and after surface treatment. The study of corrosive properties of the surface layers was performed by an electrochemical impedance spectroscopy (EIS) method. Corrosion damages were identified using impedance dependences. Findings: The microstructure of the surface layers of the V-8Ti, V-15Cr, and V-35Cr alloys in the initial state and after plasma treatment have been investigated. The chemical composition of the surface layers is determined and comparative measurements of the microhardness of these alloys are carried out. Corrosion-electrochemical properties (corrosion potentials, electrochemical impedance spectroscopy and constructed potential-dynamic polarization curves) of investigated alloys after treatment with nitrogen plasma are evaluated. Research limitations/implications: The results obtained using laboratory samples should be checked at the conditions of power equipment operation. Practical implications: This treatment has advantages over other methods of surface engineering since it provides strong surface plastic deformation and the possibility of formation of secondary phases resulting in increases in surface hardness and corrosion resistance. Originality/value: Vanadium alloys have significant advantages over other structural materials due to their high thermal conductivity and swelling resistance, high strength and plasticity up to temperatures of 700-800°C, and good weldability.
Źródło:
Archives of Materials Science and Engineering; 2020, 102, 1; 5--12
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the Influence of Vibratory Machining on Titanium Alloys Properties
Autorzy:
Bańkowski, D.
Spadło, S.
Powiązania:
https://bibliotekanauki.pl/articles/947596.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
titanium alloy
vibratory machining
finishing treatment
surface roughness
micro-hardness
stop tytanu
obróbka wibracyjna
obróbka wykańczająca
chropowatość powierzchni
mikrotwardość
Opis:
This article proposes these of vibratory machining to Ti-6Al-4V titanium alloy as finishing treatment. Titanium alloy was used in the aerospace industry, military, metallurgical, automotive and medical processes, extreme sports and other. The three-level three-factor Box-Behnken experiment examined the influence of machining time of vibratory machining, the type of mass finishing media used and the initial state of the surface layer on the mass loss, geometric structure of the surface, micro hardness and the optimal process parameters were determined. Considerations were given the surfaces after milling, after cutting with a band saw and after the sanding process. The experiment used three types of mass finishing media: polyester, porcelain and metal. Duration of vibratory machining treatment was assumed to be 20, 40, 60 minutes. The form profiles before and after vibratory machining were determined with the Talysurf CCI Lite - Taylor Hobson optical profiler. Future tests should concern research to carry out tests using abrasive pastes with a larger granulation of abrasive grains, to carry out tests for longer processing times and to determine the time after which the parameters of geometrical structure of the surface change is unnoticeable.
Źródło:
Archives of Foundry Engineering; 2020, 20, 3; 47-52
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Role of tool rotational speed on the tribological characteristics of magnesium based AZ61A/TiC composite developed via friction stir processing route
Autorzy:
Sagar, P.
Handa, A.
Powiązania:
https://bibliotekanauki.pl/articles/367279.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
friction stir processing
AZ61A magnesium alloy
microhardness
wear
proces tarciowej modyfikacji warstw wierzchnich z mieszaniem materiału
FSP
stop magnezu AZ61
mikrotwardość
zużycie
Opis:
Purpose: A new composite material was prepared and Different properties such as hardness and tribological behaviour of the fabricated metal matrix composite (MMC) was investigated and compared with the base AZ61A magnesium alloy. Design/methodology/approach: For the current research work, state-of-the-art technology, Friction stir processing (FSP) was performed to develop magnesium based AZ61A/TiC composite at optimized set of machine parameters. Findings: Increasing tool rotational speed ultimately leads in enhanced hardness, which further gives superior tribological properties as compared to base AZ61A alloy. Wear observations suggests a combination of abrasive and adhesive wear mechanism. Research limitations/implications: More microstructural and mechanical properties can be examined. Practical implications: The idea behind selecting AZ61A is mainly due to its increasing use in bicycle pedals and military equipment’s where at certain places it needs to encounter friction. In this current work, microhardness study and wear behaviour of AZ61A/TiC composite processed via FSP were examined. Originality/value: Paper is completely new and no work has been done till date considering this material and preparing composite with nanoparticles TiC.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2020, 101, 2; 60-75
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The character of the structure formation of model alloys of the Fe-Cr-(Zr, Zr-B) system synthesized by powder metallurgy
Autorzy:
Duriagina, Z. A.
Romanyshyn, M. R.
Kulyk, V. V.
Kovbasiuk, T. M.
Trostianchyn, A. M.
Lemishka, I. A.
Powiązania:
https://bibliotekanauki.pl/articles/366907.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
model alloys
phase diagram
microstructure
microhardness
XRD analysis
stop modelowy
diagram fazowy
mikrostruktura
mikrotwardość
analiza XRD
Opis:
Purpose: The purpose of the work is to synthesize and investigate the character of structure formation, phase composition and properties of model alloys Fe75Cr25, Fe70Cr25Zr5, and Fe69Cr25Zr5B1. Design/methodology/approach: Model alloys are created using traditional powder metallurgy approaches. The sintering process was carried out in an electric arc furnace with a tungsten cathode in a purified argon atmosphere under a pressure of 6·104 Pa on a water cooled copper anode. Annealing of sintered alloys was carried out at a temperature of 800°C for 3 h in an electrocorundum tube. The XRD analysis was performed on diffractometers DRON-3.0M and DRON-4.0M. Microstructure study and phase identification were performed on a REMMA-102-02 scanning electron microscope. The microhardness was measured on a PMT-3M microhardness meter. Findings: When alloying a model alloy of the Fe-Cr system with zirconium in an amount of up to 5%, it is possible to obtain a microstructure of a composite type consisting of a mechanical mixture of a basic Fe2(Cr) solid solution, solid solutions based on Laves phases and dispersive precipitates of these phases of Fe2Zr and FeCrZr compositions. In alloys of such systems or in coatings formed based on such systems, an increase in hardness and wear resistance and creep resistance at a temperature about 800°C will be reached. Research limitations/implications: The obtained results were verified during laser doping with powder mixtures of appropriate composition on stainless steels of ferrite and ferrite-martensitic classes. Practical implications: The character of the structure formation of model alloys and the determined phase transformations in the Fe-Cr, Fe-Cr-Zr, and Fe-Cr-B-Zr systems can be used to improve the chemical composition of alloying plasters during the formation of ferrite and ferrite-martensitic stainless steel coatings. Originality/value: The model alloys were synthesized and their phase composition and microstructure were studied; also, their microhardness was measured. The influence of the chemical composition of the studied materials on the character of structure formation and their properties was analysed.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2020, 100, 2; 49-57
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of the modification by ultrafine silicon carbide powder on the structure and properties of the Al-Si alloy
Autorzy:
Kovbasiuk, T. M.
Selivorstov, V. Yu.
Dotsenko, Yu. V.
Duriagina, Z. A.
Kulyk, V. V.
Kasai, O. M.
Voitovych, V. V.
Powiązania:
https://bibliotekanauki.pl/articles/1818500.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
Al-Si alloy
silicon carbide
modification
mechanical properties
microstructure
microhardness
Stop Al-Si
węglik krzemu
modyfikacja
właściwości mechaniczne
mikrostruktura
mikrotwardość
Opis:
Purpose: Determine the possibility of modifying aluminium alloys of the Al-Si system with an ultrafine SiC modifier with a particie size of 3-5 pm. Design/methodology/approach: Processing of the Al-Si alloy was carried out by introducing an ultrafine modifier in the amount of 0.1, 0.2, or 0.3 wt.%. Silicon carbide (SiC) with a particle size in the range of 3-5 pm was used as a modifier. To study the microstructure of the formed surface layers, a metallographic analysis was performed according to the standard method on a microscope MIKPOTEX® MMT-14C using TopView software. Microhardness studies of the samples were carried out on a Vickers microhardness tester NOVOTEST TC-MKV1. The microstructure of castings of the AlSi12 grade was studied at magnification from 100 to 400 times on the horizontal and vertical surfaces of the samples after etching with a 2% NaOH aqueous solution. Findings: Aluminium cast alloy of Al-Si system has been synthesized with the addition of 0.1, 0.2, and 0.3 wt.% ultrafine SiC modifier. It was found that the modification of the AlSi12 alloy by SiC particles of 3-5 pm in size led to an improvement of its microstructure due to the reduction of the volume fraction of micropores and primary Si crystals. It was shown that the AlSi12 aluminium alloy due to the modification by 0.2 wt.% SiC has the best micromechanical properties and macrostructure density. Research limitations/implications: The obtained research results are relevant for cast specimens of the indicated sizes and shapes. The studies did not take into account the influence of the scale factor of the castings. Practical implications: The developed modification technology was recommended for use in the conditions of the foundry "Dnipropetrovsk Aggregate Plant" (Dnipro, Ukraine). Originality/value: The technology of AlSi12 alloy modification of ultrafine SIC modifier with a particle size of 3-5 pm was used for the first time.
Źródło:
Archives of Materials Science and Engineering; 2020, 101, 2; 57--62
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości struktury oraz analiza porównawcza mikrotwardości przylgni zaworu wydechowego wzmacnianej stellitem oraz fazą międzymetaliczną Fe3Al
Properties of the structure and comparative analyis of microhardness of the exhaust valve face strengthened with stellite and Fe3Al intermetallic phase
Autorzy:
Garbala, Krzysztof
Cybulko, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/1845188.pdf
Data publikacji:
2020
Wydawca:
Centralny Ośrodek Badawczo-Rozwojowy Aparatury Badawczej i Dydaktycznej, COBRABiD
Tematy:
mikrotwardość
zawór wydechowy
stellit
faza międzymetaliczna
microhardness
exhaust valve
stellite
intermetallic phase
Opis:
W silnikach, w których stosuje się zasilanie sprężonym gazem ziemnym, LPG oraz innymi paliwami gazowymi, obserwuje się konieczność częstszej wymiany zaworów wydechowych. Zawory te w silnikach spalinowych mogą być eksploatowane przez krótszy czas niż ich odpowiedniki w silnikach zasilanych benzyną i olejem napędowym. Najbardziej narażona na degradację jest przylgnia zaworu wydechowego. Wynika to z temperatury spalania gazu ziemnego w komorze spalania oraz temperatury spalin mających kontakt z zaworem. W pracy przedstawiono porównawczy rozkład mikrotwardości w zaworach wydechowych napawanych fazą międzymetaliczną Fe3Al oraz stellitem.
In engines, fuelled with concentrated natural gas, LPG, and other gaseous fuels, the necessity for more frequent replacement of exhaust valves is observed. These valves in combustion engines may be operated for a shorter period than their equivalents in engines fuelled with petrol and diesel oil. The exhaust valve face is most exposed to degradation. This results from the combustion temperature of natural gas in the combustion chamber and the temperature of exhaust gas in contact with the valve. The paper presents a comparative distribution of microhardness in exhaust valves pad welded with Fe3Al intermetallic phase and stellite.
Źródło:
Aparatura Badawcza i Dydaktyczna; 2020, 25, 3; 151-164
2392-1765
Pojawia się w:
Aparatura Badawcza i Dydaktyczna
Dostawca treści:
Biblioteka Nauki
Artykuł

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