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Wyszukujesz frazę "Si-Al alloy" wg kryterium: Temat


Tytuł:
The Continuous Growth of Bulk Si by Temperature Gradient Zone Melting Method
Autorzy:
Li, Jiayan
Wang, Liang
Hao, Jianjie
Ni, Ping
Tan, Yi
Powiązania:
https://bibliotekanauki.pl/articles/356541.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
bulk Si
TGZM
Si-Al alloy
growth rate
impurities
Opis:
Temperature gradient zone melting (TGZM) method was used to obtain bulk Si continuously for the efficient separation and purification of primary Si from the Si-Al alloy in this work. The effects of alloy thickness, temperature gradient and holding time in TGZM purification technology were investigated. Finally, the continuous growth of bulk Si without eutectic inclusions was obtained. The results showed that the growth rate of bulk Si was independent of the liquid zone thickness. When the temperature gradient was changed from 2.48 K/mm to 3.97 K/mm, the growth rate of bulk Si was enhanced from 7.9×10-5 mm/s to 2.47×10-4 mm/s, which was increased by about 3 times. The bulk Si could grow continuously and the growth rate was decreased with the increase of holding time from 1 h to 5 h. Meanwhile, low refining temperature was beneficial to the removal of impurities. With a precipitation temperature of 1460 K and a temperature gradient of 2.48 K/mm, the removal rates of Fe, P and B were 99.8%, 94.0% and 63.6%, respectively.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 1; 271-278
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlation of Hardness and Silicon Morphology for Al-Si-Sb Alloy
Autorzy:
Uzun, O.
Yilmaz, F.
Emeksiz, C.
Ergen, S.
Kolemen, U.
Powiązania:
https://bibliotekanauki.pl/articles/356738.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-Si alloy
casting
Vickers
finite element analysis
Opis:
In this study, we have focused on the role of silicon morphology on the hardness of eutectic Al–12 wt.% Si–0.5 wt.% Sb alloy solidified at different cooling rates. The alloys were produced by using induction melting, arc-remelting and melt-spinning techniques. The cooling rates of the alloys were determined as 0.5, 60 and ~105°C.s-1 for induction-melted, arc-remelted and meltspun alloy. The experimental results show that as the cooling rate increased the coarse silicon phase was substantially refined and its morphology altered from sharp need-like to round shape. Two exothermic peaks, attributed to precipitation and coarsening of silicon from supersaturated α-Al, were observed in the DSC curve of MS alloy. Vicker’s hardness of melt-spun alloy was found two times higher than those of IMed and ARed alloys. The lowest hardness of induction-melted alloy was ascribed to the lamellar morphology of silicon, yielding decohesive rupture. This result was confirmed by finite element analyzing.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 1; 467-472
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Crystallization of the AlSi9 Alloy Designed for the Alfin Processing of Ring Supports in Engine Pistons
Autorzy:
Piatkowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/947636.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-Si cast alloy
alfin processing
crystallization
microstructure alloys
Opis:
This article presents a study of the crystallization and microstructure of the AlSi9 alloy (EN AC-AlSi9) used for the alfin processing of iron ring supports in castings of silumin pistons. Alfin processing in brief is based on submerging an iron casting in an Al-Si bath, maintaining it there for a defined time period, placing it in a chill mould casting machine and immersing it in the alloy. This technology is used for iron ring supports in the pistons of internal combustion engines, among others. Thermal analysis shows that when the AlSi9 alloy contains a minimal content of iron, nucleation and increase in the triple α (Al)+Fe+(Si) eutectic containing the α -Al8Fe2Si phase takes place at the end of the crystallization of the double α (Al)+ß(Si) eutectic. Due to the morphology of the ”Chinese script” the -Al8Fe2Si phase is beneficial and does not reduce the alloy’s brittleness. After approx. 5 hours of alfin processing, the -Al5FeSi phase crystallizes as a component of the α+Al5FeSi+(Si) eutectic. Its disadvantageous morphology is ”platelike” with sharp corners, and in a microsection of the surface, ”needles” with pointed corners are visible, with increases the fragility of the AlSi9 alloys.
Źródło:
Archives of Foundry Engineering; 2020, 20, 2; 65-70
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of Eutectic Formation in Al-Si Alloy Using A Phase-Field Method
Autorzy:
Ebrahimi, Z.
Powiązania:
https://bibliotekanauki.pl/articles/353792.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
phase-field model
Al-Si alloy
eutectic growth
fluctuations
Opis:
We have utilized a phase-field model to investigate the evolution of eutectic silicon in Al-Si alloy. The interfacial fluctuations are included into a phase-field model of two-phase solidification, as stochastic noise terms and their dominant role in eutectic silicon formation is discussed. We have observed that silicon spherical particles nucleate on the foundation of primary aluminum phase and their nucleation continues on concentric rings, through the Al matrix. The nucleation of silicon particles is attributed to the inclusion of fluctuations into the phase-field equations. The simulation results have shown needle-like, fish-bone like and flakes of silicon phase by adjusting the noise coefficients to larger values. Moreover, the role of primary Al phase on nucleation of silicon particles in Al-Si alloy is elaborated. We have found that the addition of fluctuations plays the role of modifiers in our simulations and is essential for phase-field modeling of eutectic growth in Al-Si system. The simulated finger-like Al phases and spherical Si particles are very similar to those of experimental eutectic growth in modified Al-Si alloy.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 4; 1969-1981
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Semisolid and Strontium Addition on Dry Sliding Wear Behavior of Hypoeutectic Al-Si Alloy
Autorzy:
Anas, Noraz Man
Zakaria, S. A.
Anasyida, A. S.
Mohamad, Hasmaliza
Dhindaw, Brij Kumar
Powiązania:
https://bibliotekanauki.pl/articles/2203750.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hypoeutectic Al-Si alloy
semisolid
cooling slope
Sr
wear resistance
Opis:
The study aims to investigate the effect of semisolid structure and strontium (Sr) addition on the wear behavior of hypoeutectic Al-Si alloy. Semisolid hypoeutectic Al-Si alloy was prepared using cooling slope casting with addition of 0 to 0.93 wt.% Sr. Microstructural study was done using an optical microscope. Vicker microhardness and pin on disc tribometer were used for microhardness and wear testing. When compared to conventional casting, the microhardness of the semisolid hypoeutectic Al-Si alloy improved by 9.8%. Sr addition at 0.43 wt.% resulted in a refined eutectic structure with a 17% increase in hardness over conventional casting. The globular structure α-Al formed during semisolid casting reduced porosity, and the addition of Sr refined the eutectic silicon into a fine fibrous structure that is tightly bound with the Al matrix. These are the primary factors that contribute to the high wear resistance in modified-Sr semisolid alloys.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 307--317
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Role of Microstructure on the Corrosion Behaviour of as cast AlCu4MgSi and MgAl2Si Alloys
Autorzy:
Lachowicz, M. M.
Jasionowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/381379.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
metallography
corrosion resistance
aluminum alloy
magnesium alloy
Al-Cu-Mg-Si alloy
Mg-Al-Si alloy
metalografia
odporność korozyjna
stop aluminium
stop magnezu
stop Al-Cu-Mg-Si
stop Mg-Al-Si
Opis:
In this work, the effect of the microstructure on corrosion behavior of selected Mg- and Al-based as cast alloys, was evaluated. The electrochemical examinations were carried out, and then a morphology of corrosion products formed due to local polarization on materials surface, was analyzed. It was documented that the presence of Mg2Si phase plays an important role in the corrosion course of Mg-based alloy. A selective etching was observed in sites of Mg2Si precipitates having “Chinese script”- like morphology. Analogous situation was found for Al-based alloy, where the key role was played by cathodic θ-CuAl2 phase.
Źródło:
Archives of Foundry Engineering; 2018, 18, 2; 125-130
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Bending Fatigue Properties of Al-Si Cast Alloy
Autorzy:
Tillová, E.
Závodská, D.
Kuchariková, L.
Chalupová, M.
Belan, J.
Powiązania:
https://bibliotekanauki.pl/articles/355910.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
secondary Al-Si cast alloy
fatigue properties
fracture
cast defects
Opis:
Fatigue properties of casting Al-alloys are very sensitive to the microstructural features of the alloy (e.g. size and morphology of the eutectic Si, secondary dendrite arm spacing – SDAS, intermetallics, grain size) and casting defects (porosity and oxides). Experimental study of bending fatigue properties of secondary cast alloys have shown that: fatigue tests up to 106-107cycles show mean fatigue limits of approx. 30-49 MPa (AlSi9Cu3 alloy – as cast state), approx. 65-76 MPa (AlSi9Cu3 alloy after solution treatment) and 60-70 MPa (self-hardened AlZn10Si8Mg alloy) in the tested casting condition; whenever large pore is present at or near the specimen’s surface, it will be the dominant cause of fatigue crack initiation; in the absence of large casting defects, the influence of microstructural features (Si morphology; Fe-rich phases) on the fatigue performance becomes more pronounced.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1591-1596
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Combustion Engine Cylinder Liners Made of Al-Si Alloys
Autorzy:
Orłowicz, A. W.
Tupaj, M.
Mróz, M.
Trytek, A.
Powiązania:
https://bibliotekanauki.pl/articles/382953.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
combustion engine
cylinder liner
Al-Si alloy
silnik spalinowy
tuleja cylindrowa
stop Al-Si
Opis:
The paper deals with problems related to application of aluminum-silicon alloys for combustion engine cylinder liners.
Źródło:
Archives of Foundry Engineering; 2015, 15, 2; 71-74
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improvement of Al-Si Alloy Fatigue Strength by Means of Refining and Modification
Autorzy:
Tupaj, M.
Orłowicz, A. W.
Trytek, A.
Mróz, M.
Powiązania:
https://bibliotekanauki.pl/articles/379844.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-Si alloy
fatigue limit
refining
modification
stop Al-Si
granica zmęczenia
rafinacja
modyfikacja
Opis:
The paper presents results of a study concerning an AlSi7Mg alloy and the effect of subjecting the liquid metal to four different processes: conventional refining with hexachloroethane; the same refining followed by modification with titanium, boron, and sodium; refining by purging with argon carried out in parallel with modification with titanium and boron salts and strontium; and parallel refining with argon and modification with titanium, boron, and sodium salts. The effect of these four processes on compactness of the material, parameters of microstructure, and fatigue strength of AlSi7Mg alloy after heat treatment. It has been found that the highest compactness (the lowest porosity ratio value) and the most favorable values of the examined parameters of microstructure were demonstrated by the alloy obtained with the use of the process including parallel purging with argon and modification with salts of titanium, boron, and sodium. It has been found that in the fatigue cracking process observed in all the four variants of the liquid metal treatment, the crucial role in initiation of fatigue cracks was played by porosity. Application of the process consisting in refining by purging with argon parallel to modification with Ti, B, and Na salts allowed to refine the microstructure and reduce significantly porosity of the alloy extending thus the time of initiation and propagation of fatigue cracks. The ultimate effect consisted in a distinct increase of the fatigue limit value.
Źródło:
Archives of Foundry Engineering; 2019, 4; 61-66
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Water Mist Cooling of Casting Die on the Solidification, Microstructure and Properties of AlSi20 Alloy
Autorzy:
Władysiak, R.
Kozuń, A.
Pacyniak, T.
Powiązania:
https://bibliotekanauki.pl/articles/353825.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
silicon dendrites
casting die cooling
water mist
hypereutectic Al-Si alloy
Opis:
Unmodified AlSi20 alloy were casted at the research station, allowing for sequential multipoint cooling using a dedicated computer- controlled program. This method allows for the formation of the microstructure of hypereutectic AlSi20 alloy and also increases hardness. Primary silicon dendrites were found in the microstructure of cooled samples. Based on these dendrites, the formation of primary silicon particles is explained. Cooling of casting die with a water mist stream causes changes in solidification, which leads to expansion of the boundary layer with columnar crystals and shrinkage of the core zone with equiaxed crystals. It also causes more regular hardness distribution around pre-eutectic Si crystals, which can lead to tensile strength and machinability improvement.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 1; 187-194
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Trace Elements (Co, Cr) on the Microstructure and Physical Properties of Al-Si-Cu-Mg-Fe Extruded Alloy
Autorzy:
Ahn, S. S.
Sharief, P.
Lee, C. H.
Son, H. T.
Kim, Y. H.
Kim, Y. C.
Hong, S.
Hong, S. J.
Powiązania:
https://bibliotekanauki.pl/articles/352787.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-Si alloy
microstructure
extrusion
coefficient of thermal expansion
trace elements
Opis:
Trace elements Co, Cr were added to investigate their influence on the microstructure and physical properties of Al-Si extruded alloy. The Co, Cr elements were randomly distributed in the matrix, forms intermetallic phase and their existence wereconfirmed by XRD, EDS and SEM analysis. With addition of trace elements, the microstructure was modified, Si particle size was reduced and the growth rate of β-(Al5 FeSi) phase limited. Compared to parent alloy, hardness and tensile strength were enhanced while the linear coefficient of thermal expansion (CTE) was significantly reduced by 42.4% and 16.05% with Co and Cr addition respectively. It is considered that the low CTE occurs with addition of Co was due to the formation of intermetallic compound having low coefficient of thermal expansion. The results suggested that Co acts as an effective element in improving the mechanical properties of Al-Si alloy.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 3; 857-862
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical Modification of Al-6%Si By Semisolid Process
Autorzy:
Sarajan, Z.
Powiązania:
https://bibliotekanauki.pl/articles/353078.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical properties
Al-6%Si Alloy
stirring
morphology
semisolid process
Opis:
In this study by semisolid processing of Al-6%Si alloy, it has been found that small additions of Ti-6Al-4V shift the liquidus temperature up and the recalescence decreases. The nucleation event takes place at higher temperatures. Furthermore, the rate at which growth temperature increases is less than that of nucleation temperature and therefore more nuclei form with less potential for growth. In this processing refiner increases the α-Al percentage and reduces globule size. Improvement of mechanical property and microstructure characterization are the main advantages of this study.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 3; 1689-1696
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Cooling Rate on Intergranular Corrosion in Al-Si7-Mg Alloy
Autorzy:
Bernat, L.
Powiązania:
https://bibliotekanauki.pl/articles/381720.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al-Si-Mg alloy
intergranular corrosion
cooling rate
stop Al-Si-Mg
korozja międzykrystaliczna
szybkość chłodzenia
Opis:
The use of aluminium cast alloys in automotive industry results from a tendency to considerably lower vehicle mass. Subject to working conditions, silumin casts may show occurrence of intergranular corrosion that reduces mechanical properties of the parts produced. The paper presents the influence of cooling rate – R of a plate cast of aluminium alloy EN AC-AlSi7Mg0,3 on the depth of appearance of intergranular corrosion. Samples were exposed to corrosive medium by immersion for 2,5; 12; 24 and 48 hours in an aqueous solution of NaCl+HCl+H2O. The study demonstrated that cooling rate – R and subsurface porosity significantly influence on distribution and depth of intergranular corrosion in casts of subeutectic silumin.
Źródło:
Archives of Foundry Engineering; 2015, 15, 3 spec.; 107-111
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Plasma Coatings on Aluminium-Silicon Alloy Surfaces
Autorzy:
Długosz, P.
Garbacz-Klempka, A.
Piwońska, J.
Darłak, P.
Młynarczyk, M.
Powiązania:
https://bibliotekanauki.pl/articles/2079836.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
plasma coating
Al-Si alloy
plasma oxidation
anodizing
powłoki plazmowe
stop Al-Si
utlenianie plazmowe
anodowanie
Opis:
Plasma oxidation, similarly to anodic oxidation (anodizing), are classified as electrochemical surface treatment of metals such as Al, Mg, Ti and their alloys. This type of treatment is used to make surface of castings, plastically processed products, shaped with incremental methods to suitable for certain requirements. The most important role of the micro plasma coating is to protect the metal surface against corrosion. It is well known that coating of aluminium alloys containing silicon using anodic oxidation causes significant difficulties. They are linked to the eutectic nature of this alloy and result in a lack of coverage in silicon-related areas. The coating structure in these areas is discontinuous. In order to eliminate this phenomenon, it is required to apply oxidation coatings using the PEO (Plasma Electrolytic Oxidation) method. It allows a consistent, crystalline coating to be formed. This study presents the mechanical properties of the coatings applied to Al-Si alloy using the PEO method. As part of the testing, the coating thickness, microhardness and scratch resistance were determined. On the basis of the results obtained, it was concluded that the thickness of the coatings complies with the requirements of conventional anodizing. Additionally, microhardness values exceeded the results obtained with standard methods.
Źródło:
Archives of Foundry Engineering; 2021, 21, 3; 96-101
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Casting pore characterization by X-ray computed tomography and metallography
Charakteryzacja porów odlewniczych metodami rentgenowskiej tomografii komputerowej i metalografii
Autorzy:
Fintová, S.
Anzelotti, G.
Konečná, R.
Nicoletto, G.
Powiązania:
https://bibliotekanauki.pl/articles/139863.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
zmęczenie
techniki metalograficzne
stopy Al-Si
tomografia rentgenowska
fatigue
metallographic techniques
Al-Si alloy
X-ray tomography
Opis:
Casting porosity is the main factor influencing the fatigue properties of Al-Si alloys. Due to the increasing use of aluminum castings, porosity characterization is useful for estimating their fatigue strength. In principle, a combination of metallographic techniques and statistical pore analysis is a suitable approach for predicting the largest defect size that is critical for the casting. Here, the influence of modifiers and casting technology on the largest pore size population in AISi7Mg alloy specimens is obtained and discussed adopting the Murakami's approach. However, porosity evaluation is a challenge in the case of microshrinkage pores, which are frequently found in industrial castings. Their complicated morphology prevents a reliable definition of an equivalent defect size based on metallographic techniques. This contribution reports the application of X-ray tomography to the 3D reconstruction of real pores in cast Al-Si alloys and provides insight into the complication of microshrinkage pore sizing by metallography.
Porowatość odlewów jest głównym czynnikiem wpływającym na właściwości wytrzymałościowe stopów Al-Si. Z uwagi na rosnące zastosowanie odlewów aluminiowych, charakteryzacja ich porowatości nabiera znaczenia dla oceny wytrzymałości zmęczeniowej. Uważa się, że właściwym podejściem jest zastosowanie kombinacji technik metalograficznych i statystycznej analizy porów, co umożliwia przewidywanie największego, krytycznego dla odlewu, rozmiaru defektów. W tej pracy wyznaczano i dyskutowano wpływ modyfikatorów i technologii odlewania na największy rozmiar populacji porów w próbkach stopu AlSi7Mg, przyjmując podejście Mirakami'ego. Ocena porowatości staje się jednak wyzwaniem w przypadku porów związanych z. mikrokurczliwością, które występują często w odlewach przemysłowych. Ich skomplikowana morfologia powoduje, że trudno jest wiarygodnie zdefiniować równoważny rozmiar defektu w oparciu o techniki metalograficzne. Przedstawione doniesienie zawiera opis zastosowania rentgenowskiej tomografii komputerowej do trójwymiarowej rekonstrukcji rzeczywistych porów w odlewie ze stopu AISi i daje pogląd na temat komplikacji w wymiarowaniu porów związanych z mikrokurczliwością metodami metalograficznymi.
Źródło:
Archive of Mechanical Engineering; 2010, LVII, 3; 263-273
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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