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1

Selected microstructural phenomena in FSW joints

Wciślik Wiktor

Structure and Environment

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2024

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Vol. 16, no. 2

97--110

EN

The article is a literature review on selected phenomena leading to microstructural changes in material welded using the friction stir welding (FSW) method. Particular attention was paid to the phenomena of grains recrystallization, as well as dissolution and reprecipitation of second phase particles, resulting from temperature changes during FSW. Temperature transformations in different zones of the FSW joints were characterized. The role of base material phase transformation in the formation of new particles is discussed. In the tested aluminum alloys and stainless steels, this process was particularly intensified in the heat affected zone (HAZ). In areas subjected to high temperature and significant plastic deformation (nugget zone and thermomechanically affected zone), this phenomenon did not occur or was characterized by small intensity. It was indicated that the phenomenon of particle formation clearly affects the strength parameters of the joint.

PL

W artykule przedstawiono przegląd literatury dotyczący wybranych zjawisk prowadzących do zmian mikrostrukturalnych w metalach spawanych metodą zgrzewania tarciowego (FSW). Szczególną uwagę zwrócono na zjawiska rekrystalizacji ziaren oraz rozpuszczania i ponownego wytrącania cząstek drugiej fazy, zachodzące jako efekt zmian temperatury podczas FSW. Scharakteryzowano zmiany temperatury w różnych strefach złączy FSW. Omówiono rolę przemian fazowych materiału podstawowego w powstawaniu nowych cząstek. W badanych stopach aluminium i stalach nierdzewnych proces ten był szczególnie nasilony w strefie wpływu ciepła (SWC). W obszarach narażonych na działanie wysokiej temperatury i znacznych odkształceń plastycznych (jądro zgrzeiny i strefa uplastycznienia termomechanicznego) zjawisko to nie występowało lub charakteryzowało się niewielkim natężeniem. Wykazano, że zjawisko tworzenia cząstek wyraźnie wpływa na parametry wytrzymałościowe złącza.

2

Hardness, corrosion behavior, and microstructure of Al-Cu-Mg alloy as a function of 0.3 wt.% Zr addition

Saad Karrar, Al-Murshdy Jassim M. Salman

Diagnostyka

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2023

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Vol. 24, No. 1

art. no. 2023104

EN

The effect of adding zirconium (Zr) as an alloying element to Al-Cu-Mg alloy on the hardness and corrosion of this alloy was investigated. The hardness and polarization test results of samples treated for various periods by aging at 423.15 K for 3hr showed a significant increment in the Brinell hardness (HBW) improvement ratio of 115.6% (from 45HBW to 97HBW) and an extreme reduction the corrosion rate of the alloy after Zr adding decrease in the current density by 79.42% (from 56.50 µA cm-2 to 11.63 µA cm-2) with aging for 3 hr compared to the base alloy. The impact of this addition is also reflected in the strengthening, recrystallization, and modification of the grain microstructure. These changes were clearly demonstrated by microscopic testing and proves that the addition of Zr has a considerable synergistic effect causing inhibition of recrystallization and refinement of grain size.

3

Supercritical antisolvent method for recrystallization of HMX

Thakur Anupama, Taniya, Soni Pramod, Seema Mahesh, Deshwal Seema

Chemical and Process Engineering

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2022

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Vol. 43, nr 2

165--170

EN

Supercritical antisolvent (SAS) method is an emerging technique for particle processing of high energetic materials. The study investigates the recrystallization of high energy material HMX (octahydro- 1,3,5,7-tetranitro-1,3,5,7-tetrazocine) using SAS method. The effect of pressure, solution flow rate, supercritical antisolvent flow rate and temperature on particle size and morphology of HMX crystals has been studied with acetone as solvent and supercritical carbon dioxide as antisolvent. Stable and desirable 𝛽- polymorphic form of HMX could be obtained under certain process conditions and has been confirmed by FTIR spectroscopy. The experimental results show that 𝛽- polymorph of HMX is of rhombohedral morphology with mean particle size of 13.7 μm, as confirmed by SEM and particle size analyzer respectively.

4

Transformation of structure during friction stir welding

Vakulenko Igor Alex, Plitchenko Sergey, Kurt Bulent, Proydak Svetlana, Askerov Hangardas

Zeszyty Naukowe. Transport / Politechnika Śląska

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2021

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z. 111

181--191

EN

In comparison with low carbon steels, there is increased interest in the use of aluminium-based alloys as materials for the manufacture of welded structures rolling stock of railway transport. During friction stir welding aluminium-based alloy, against the background of the analysis structural transformations, issues of development hardening processes are considered. Under conditions of existence, a temperature gradient at zone of weld formation, shown degree approximation alloy to the conditions of superplastic flow and influence from presence particles of the second phase on grain size of matrix is estimated. Evaluation of the separate influence grain size of matrix and state of solid solution at total hardness of the weld showed dependence of their contributions on temperature of hot plastic deformation. As the temperature of plastic deformation of alloy at area of the weld increases, contribution to the total hardness from grain size increase and on state of the solid solution decreases.

5

Experimental characterization of the AA7075 aluminum alloy using hot shear compression test

Bhujangrao Trunal, Veiga Fernando, Froustey Catherine, Guérard Sandra, Iriondo Edurne, Darnis Philippe, Mata Franck Girot

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 2

95--111

EN

The experimental characterization of the material under shear loading is essential for researchers to study the plastic behavior of materials during manufacturing processes. Indeed, regardless of the loading mode, ductile materials mainly deform plastically under shear loading. Thus, for such material behavior analysis, shear tests are very useful. In this paper, a test procedure is defined to characterize the shear deformation of AA7075 aluminum alloy at high strain under compression loading. The Finite Element (FE) simulation is used to select the suitable specimen geometry for the testing. Finally, the experimental tests are carried out using a conventional compression device at a constant strain rate of 0.1 s−1 and at an elevated temperature of 20–500 °C. The results show that the drop in the flow stress curved relative to the increase in temperature exhibits the softening mechanism. The homogeneous behavior of the shear strain along the shear region was also observed and shown by the macro and micro images. The effect of temperature and equivalent strain on the evolution of the microstructure is discussed in detail. It is discovered that, various dynamic recrystallization mechanisms were recorded for aluminum alloy AA7075 depending on the imposed strain conditions.

6

Adiabatic shearing mechanism on Al-4.2%Cu alloy bars subjected to electromagnetic loading

Zhang Xu, Huang Yunkai, Meng Shengfei, Zhu Congcong, Li Guangyao, Cui Junjia

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 1

393--405

EN

This paper proposed an electromagnetic loading process with the high-speed impact. Al-4.2% Cu alloy bars were used to employ electromagnetic impact (EI) experiments. Deformation mechanism and microstructure evolution of EI samples were revealed by theoretical model and microstructure characterizations. The EI process had impact force (peak value 40 kN) and impact velocity (peak value 6.7 m/s) during a short time period (1.25 ms). Adiabatic shearing mechanism dominated the whole deformation process, causing that significant microstructure characteristic was adiabatic shear bands (ASBs). The theoretical analysis implied that the formation of ASBs was accounted for the radial velocity gradient. Most plastic deformations concentrated in ASBs, and approximately pure shear deformations resulted in adiabatic temperature rise of 0.33–0.42 Tm inside ASBs. The width of ASBs was about 135 μm, in which original equiaxial grains were elongated into laminated sub-structures. TEM observations showed multi-slip systems were simultaneously actuated due to severe shear deformations. High dislocation density and dislocation tangles distributed with the ASBs. Adiabatic temperature rise and distorted energies drove sub-grains rotate into recrystallization grains (70–280 nm) with large angle grain boundaries. The needed maximum time (45 μs) for rotational dynamic recrystallization was far less than that of plastic deformation, indicating that rotational dynamic recrystallization mechanism contributed to the formation of recrystallization grains.

7

Microstructural evaluation of the high-frequency induction welded joints of low carbon steel pipes

Bunsch Adam, Krawczyk Janusz, Matusiewicz Piotr

Advances in Materials Science

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2021

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Vol. 21, nr 4(70)

19--33

EN

The work presents the results of research on the structure of welded joints in the area of heat affected zone (HAZ). Based on precisely performed metallographic tests, the contribution of individual structural components in the area of welds of pipes welded with the induction method was assessed. The volume fraction of individual structural components in various areas of the heat affected zone, the size of the grain formed in the welding process, as well as its shape coefficients were determined. On the basis of metallographic observations, an attempt was made to describe the course of the pressure induction welding process, taking into account the structural changes, phase changes and the recovering and recrystallization processes taking place in this process.

8

Microstructure evolution and property analysis of commercial pure Al alloy processed by radial-shear rolling

Gamin Yu. V., Akopyan T. K., Koshmin A. N., Dolbachev A. P., Goncharuk A. V.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

674--683

EN

The features of microstructure formation and properties of commercial pure aluminum alloy (Al 99.5%) obtained by radial-shear rolling (RSR) method at the different heating temperatures of 25, 200, 250, 300 and 350 °C were examined. In this paper, the rods with diameter of 14 mm were obtained from initial billet with diameter of 60 mm in five passes. The microstructure analysis with electron backscatter diffraction (EBSD), measurements of microhardness HV over cross-section, and tension test for determination of mechanical properties were carried out for these rods. The FEM simulation of RSR process and calculation of Zener–Hollomon parameter (Z) were carried out with Software QFORM. The obtained rods have the gradient microstructure typical of RSR characterized by surface layer with ultrafine grain structure (UFG) and grain size from 0.3 to 5 µm. In the central part of rod, the fiber deformed structure with minimal fraction of recrystallized grains (< 5%) is formed. This combination is optimal for simultaneous achievement of high strength (UTS ~ 107–110 MPa; YS ~ 100–109 MPa; ~ 35–40 HV) and ductility (El ~ 15–30%). The most intensive growth of plastic properties is observed at rolling temperatures close to the temperature of the onset of recrystallization, it is associated with additional deformational heating of surface layers and the formation of partially recrystallized structure. The obtained distribution dependences of average size of dynamic recrystallized grain on Zener–Hollomon parameter showed that the decrease in parameter Z leads to the increase in size of recrystallized grain for RSR process.

9

Emami S., Sadeghi-Kanani S., Saeid T., Khan F.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

498--513

EN

Dissimilar joints of AISI 430 ferritic and AISI 304L austenitic stainless steels were produced by friction stir welding process. A sound and defect-free joint was obtained at 1 mm tool offset towards the ferritic sample located in the advancing side, and at rotational and welding speeds of 560 rpm and 50 mm/min, respectively. The XRD measurements revealed the presence of approximately equal volume fractions of ferrite (51%) and austenite (49%) phases in the stir zone (SZ). The formation of low-angle grain boundaries through the occurrence of dynamic recovery along with the presence of shear texture components in both constituent phases of ferrite and austenite in the SZ approved the occurrence of continuous dynamic recrystallization throughout the evolved microstructure. Moreover, microstructural observations showed the formation of necklace structure through the microstructure of ferrite in the SZ. Taylor map approved the strain localization in the ferrite phase. Micro-hardness measurement indicated that the hardness value is increased in the SZ. The result of tensile test showed that fracture occurred from less ductile ferritic base metal.

10

Characterisation of Purified Gypsum and Insoluble Impurities Obtained from Phosphogypsum Waste

Kaludjerovic Lazar, Isek Josip, Vukovic Nikola, Milosevic Maja

Inżynieria Mineralna

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2019

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R. 21, nr 1

73--78

EN

In this study, the chemical and phase composition of two samples of phosphogypsum from the waste dumps of the Industry of Chemical Products “Elixir – Prahovo” (Serbia) were examined, as well as the possibility of recrystallization of gypsum from an aqueous suspension of phosphogypsum. The negative effect of higher temperatures on the solubility of calcium sulfate (13.08 mmol/dm3 at 95°C vs. 15.43 mmol/dm3 at 40°C) was utilized. In several repeated cycles, calcium sulfate component was progressively dissolved in water at room temperature and then precipitated at 100°C, using the same liquid phase throughout the experiment. Therefore, phosphogypsum was separated into recrystallized (purified) gypsum, insoluble residue and supernatant, and the mass balance for the experiment was calculated. Elemental, XRD and SEM-EDS analyses were performed on raw phosphogypsum, purified gypsum and insoluble residue. The whiteness of raw phosphogypsum and purified gypsum were determined and compared. The main objective of the study was to investigate the nature of insoluble impurities, in order to define and optimize the methods for their removal during a potential industrial processing of phosphogypsum.

PL

W artykule przedstawiono skład chemiczny i fazowy dwóch próbek fosfogipsu ze składowisk odpadów Przemysłu Chemicznego „Elixir – Prahovo” (Serbia), a także możliwość rekrystalizacji gipsu z zawiesiny wodnej fosfogipsu. Wykorzystano negatywny wpływ wyższych temperatur na rozpuszczalność siarczanu wapnia (13,08 mmol/ dm3 w 95°C wobec 15,43 mmol/dm3 w 40°C). W kilku powtarzających się cyklach siarczanu wapnia stopniowo rozpuszczano w wodzie w temperaturze pokojowej, a następnie wytrącano w 100°C, stosując tę samą fazę ciekłą w całym doświadczeniu. W ten sposób fosfogips został rozdzielony na rekrystalizowany (oczyszczony) gips, nierozpuszczalną pozostałość i supernatant, kolejno obliczono bilans masy dla doświadczenia. Analizy elementarne, XRD i SEM-EDS przeprowadzono na surowym fosfogipsie, oczyszczonym gipsie i nierozpuszczalnej pozostałości. Określono i porównano biel surowego i oczyszczonego gipsu. Głównym celem pracy było zbadanie natury nierozpuszczalnych zanieczyszczeń w celu określenia i zoptymalizowania metod ich usuwania podczas przemysłowego przetwarzania fosfogipsu.

11

Analysis of the strengthening and recrystallization of electrolytic copper (Cu-ETP) and oxygen free copper (Cu-OF)

Zasadzińska Małgorzata, Knych Tadeusz, Strzępek Paweł, Jurkiewicz Bartosz, Franczak Krystian

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 1

186--193

EN

The research paper studies the strengthening and the kinetics of recrystallization of ETP copper and OF copper. This research covers a wide scope of strain hardening specific for the manufacturing of microwires (true strain of the order of 5) and the range of temperatures and times of the recrystallization process referring to the real life conditions occurring in advanced technologies of microwires’ manufacturing. As a result of the performed tests, it was established that the recrystallization temperature of ETP copper is lower than the recrystallization temperature of OF copper regardless of the recrystallization time as the recrystallisation effect can be achieved after about 10–30 s regardless of the copper grade.

12

Re-crystallization of Silicon during Rapid Thermal Treatment

Gorushko V., Omelchenko A., Pilipenko V., Solodukha V., Opielak M., Żukowski P., Kołtunowicz T.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 5

196--198

EN

It is by means of the Auger-spectroscopy, spectral ellipsometry, X-ray diffraction that for the first time an opportunity was shown of applying the rapid thermal treatment for removal of the disrupted layer on the working surface of the silicon wafers after the chemical-mechanical polishing owing to its solid-phase re-crystallization.

PL

Dzięki użyciu spektroskopii Augera, elipsometrii spektralnej oraz dyfrakcji rentgenowskiej po raz pierwszy przedstawiona została możliwość zastosowania szybkiego termicznego usuwania uszkodzonej warstwy na powierzchni roboczej wafli silikonowych, powstałych po chemiczno-mechanicznym polerowaniu, za pośrednictwem jego rekrystalizacji w fazie stałej.

13

Struktura i własności mechaniczne prętów ze stopu AA7010 w stanach O i T6

Pieła K., Sak T., Błaż L., Woźnicki A., Ostachowski P., Łagoda M.

Obróbka Plastyczna Metali

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2018

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T. 29, nr 2

169--192

PL

Wyciskane na gorąco pręty ze stopu aluminium AlZn6,43Mg2,23Cu1,78 (AA7010) poddano, kolejno, odkształceniu drogą ciągnienia, wyżarzaniu na stan miękki (O) oraz procesowi utwardzania wydzieleniowego na stan T6. Próbki ciągnionych prętów o zróżnicowanej wielkości odkształcenia (5–67%) poddano wyżarzaniu w szerokim zakresie temperatury (300–465°C) i czasu wyżarzania (1–10 h). Zastosowane warunki wyżarzania aktywizują procesy zdrowienia, rekrystalizacji i rozrostu ziarna. Wykazano, że proces rekrystalizacji prętów, wyżarzanych na stan O, jest kontrolowany przez dystrybucję i stabilność termiczną wydzieleń fazy czynnej η (MgZn2). Wyżarzanie w temperaturze niższej od temperatury granicznej rozpuszczalności fazy czynnej (poniżej 400°C) zachowuje liniowy rozkład wydzieleń tej fazy, co utrudnia migrację frontów rekrystalizacji w kierunku promieniowym prętów i prowadzi do formowania ziaren o dużej anizotropii kształtu. Wzrost temperatury wyżarzania powoduje istotne przyśpieszenie procesu rozpuszczania wydzieleń fazy czynnej, w wyniku czego następuje uwolnienie frontów rekrystalizacji, a w konsekwencji formowanie ziaren o znacznie mniejszej anizotropii kształtu oraz zmiana dystrybucji i morfologii wydzieleń tej fazy. Stwierdzono ponadto, że – pomimo znaczących różnic strukturalnych – wielkość odkształcenia praktycznie nie wpływa na własności wytrzymałościowe i plastyczne prętów zarówno w stanie O, jak i w większości przypadków w stanie T6. Potwierdzono eksperymentalnie słabą zależność własności wytrzymałościowych Al i jego stopów od wielkości ziarna oraz istotny wpływ rodzaju i dystrybucji prowydzieleń (wydzieleń) faz umacniających na własności mechaniczne tych stopów w stanie T6.

EN

The hot extruded rods of aluminum alloy AlZn6,43Mg2,23Cu1,78 (AA7010) were subjected to, in sequence, deformation by drawing, annealing to the O temper and precipitation hardening to the T6 temper. The samples of rods drawn with the variable strain value (area reduction of 5–67%), were annealed in the wide range of temperatures (300–465°C) and times (1–10 h). The applied annealing conditions activate recovery, recrystallization and grain growth processes. It was shown that recrystallization process of rods annealed to the O temper is controlled by a distribution and thermal stability of active phase η (MgZn2). The annealing at the temperatures lower than the temperature of active phase solubility limit (below 400°C) maintains a linear distribution of this phase precipitates. It hinders recrystallization fronts migration in radial direction of rods and leads to formation of grains with considerable shape anisotropy. The increase of annealing temperature results in significant acceleration of the active phase precipitates dissolution process, whereby a release of recrystallization fronts and in consequence formation of grains with appreciable lower shape anisotropy, as well as change of distribution and morphology of mentioned phase precipitates take place. Moreover, it was found that – despite considerable structural differences – strain value during drawing hardly influences strength and plastic properties of the rods in the O temper, as well as in the most cases in the T6 temper. The weak relationship between grain size and strength properties of Al and its alloys, as well as significant influence of hardening phases pre-precipitates (precipitates) type and distribution on mechanical properties of these alloys in the T6 temper were experimentally confirmed.

14

Kinetics of static recrystallization in the coarse-grained Fe–40 at.%Al–Zr–B alloy

Schindler I., Kopeček J., Kawulok P., Jabłońska M., Hadasik E., Jóźwik P., Opěla P., Hanus P., Polkowski W., Bojar Z.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 4

816--826

EN

The aim of works was to describe mathematically the kinetics of static recrystallization of the alloy type Fe–40 at.%Al–Zr–B (with 24.6 Al–0.01 B–0.18 Zr–0.01 C in wt.%) with the coarse-grained structure. The microstructure of the laboratory castings made of this extremely brittle alloy was homogenized by hot rolling of the material in the protective capsules and by the long-term annealing at 1200 °C. An initial microstructure with average grain size 0.77 ± 0.27 mm was obtained. Based on the isothermal plastic deformation tests and EBSD analysis, the static recrystallization kinetics of the prepared coarse-grained B2 iron aluminide after strain 0.20 was mathematically described. Recrystallized fraction depends on deformation/annealing temperature (900–1100 °C) as well as on annealing time. The activation energy of static recrystallization was calculated as 255 kJ mol−1. Competition between dynamic recovery and static recrystallization was proved after strain 0.35 and annealing temperature 1100 °C. Static recrystallization starts relatively easily in the studied alloy, but a very long-term annealing is quite necessary for the complete course of recrystallization. The mean size of recrystallized grains falls with the decreasing annealing temperature (0.47 ± 0.15 mm for temperature 1100 °C, and 0.22 ± 0.04 mm for 900 °C). Even at a temperature of 1200 °C the annealing after deformation should last approx. 1 min for obtaining the fully recrystallized microstructure. That is why the standard hot forming technologies should be combined by an interpass annealing in order to refine sufficiently the coarse grains.

15

Wpływ stabilizatorow na ograniczenie rekrystalizacji w lodach typu sorbet

Kamińska-Dwórznicka A., Samborska K., Jakubczyk E., Gondek E.

Przemysł Spożywczy

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2016

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T. 70, nr 9

32--35

PL

W artykule porownano wpływ mieszanek stabilizujących na przebieg procesu rekrystalizacji w sorbetach truskawkowych bezpośrednio po przygotowaniu oraz po miesiącu przechowywania w temp. -18°C. Do badań wykorzystano zdjęcia kryształów lodu wykonane za pomocą mikroskopu i kamery Nikon przystosowanych do pracy w ujemnej temperaturze. Następnie zdjęcia przeanalizowano stosując program NIS Elements D i określono wymiary średnic powstałych kryształów lodu. W badaniu jako dodatki stabilizujące zastosowano preparaty żelatyny wieprzowej, gumy guar, gumy ksantanowej, mączki chleba świętojańskiego, kappa-karagenu oraz alkoholu, naturalne białko ochronne AFP i przemysłową mieszankę stabilizatorów oznaczaną jako CRE. Stwierdzono, że dodatek AFP (w połączeniu z żelatyną i gumą guar) oraz mieszanka CRE najskuteczniej hamowały proces rekrystalizacji, a kryształy lodu po miesiącu przechowywania nie były większe niż 15 μm.

EN

The aim of the present paper was to evaluate and compare the effect of stabilizing mixtures on the run of recrystallization process in strawberry sorbet directly after preparation and after a month of storage at -18°C, using a microscope and a Nikon camera adapted to take pictures at the temperature below zero. The images were then analyzed, using NIS Elements D program to determine equivalent ice crystals’ diameters. In the present study, gelatin, guar gum, xanthan, locust bean gum, κ – carrageenan, alcohol, and natural protective protein, called AFP and the mixtures of stabilizers under the trade name CRE were used as stabilizing additives. It was found that the addition of AFP (in combination with gelatin and guar gum) and CRE mixture inhibited most effectively the recrystallization process and the ice crystals after one month of storage did not exceed 15 μm.

16

Analiza kinetyki rekrystalizacji po odkształceniu za pomocą metody relaksacji naprężenia

Pidvysots'kyy V., Kuziak R.

Prace Instytutu Metalurgii Żelaza

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2016

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T. 68, nr 2

10--16

PL

Głównym celem niniejszej pracy było poddanie weryfikacji metody relaksacji naprężenia do analizy procesów rekrystalizacji zachodzących po odkształceniu. W artykule przedstawiono wyniki badań relaksacji naprężeń oraz ilościowego pomiaru struktury. W oparciu o uzyskane dane stwierdzono że metoda relaksacji naprężeń pozwala określić kinetykę rekrystalizacji po odkształceniu i wyeliminować wpływ zdrowienia w procesie odbudowy struktury.

EN

The main objective of this work was to verify the stress relaxation method for the analysis of recrystallisation processes occurring after deformation. The article presents the results of stress relaxation and quantitative measurement of the structure. Based on the obtained data, it was found that the stress relaxation method allows to determine the kinetics of recrystallisation after deformation and to eliminate the impact of recovery in the process of structure rebuilding.

17

Walcowanie wysokotemperaturowe taśm ze stopu na osnowie fazy międzymetalicznej Ni3Al

Jóźwik P., Polkowski W., Rusz S., Schindler I., Mikuszewski T., Bojar Z.

Hutnik, Wiadomości Hutnicze

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2016

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Vol. 83, nr 9

401--405

PL

W pracy przedstawiono wyniki badań efektów walcowania wysokotemperaturowego taśm ze stopu na osnowie fazy międzymetalicznej Ni3Al z dodatkami stopowymi cyrkonu i boru. Proces odkształcania plastycznego realizowano w dwóch etapach, w temperaturze 1000 i 1100OC z prędkością obwodową walców roboczych 4, 10 i 15 m/min. Efekty przebudowy struktury obserwowano przy użyciu skaningowej mikroskopii elektronowej sprzężonej z układem do analizy dyfrakcji elektronów wstecznie rozporoszonych (EBSD), a także wykonano pomiary twardości. Stwierdzono przebudowę struktury taśm na drodze rekrystalizacji dynamicznej, której udział rósł wraz ze wzrostem prędkości i temperatury walcowania. Najsilniejsze efekty dynamicznej odbudowy struktury (powyżej 50% objętości taśm z parametrem GOS < 2O) obserwowano po drugim etapie walcowania wysokotemperaturowego realizowanego w temperaturze 1100OC z prędkością 15 m/min.

EN

The results of high temperature rolling of Ni3Al-based strips with zirconium and boron addition are shown in the paper. The deformation process was realized by two step rolling at temperature 1000 and 1100OC, with a speed: 4, 10 or 15m/min. The effects of Ni3Al strips structure rebuilding were observed by using a scanning electron microscopy coupled with an electron backscatter diffraction system (EBSD) and a hardness tests were done. The effects of growing up participation of recrystallization with rising a temperature and speed rolling were obtained. The largest effects of dynamic processes of structure recovery (approx. 50% of alloy volume with GOS < 2O) was observed after the second stage of the high temperature rolling conducted at the temperature of 1100°C with the speed of 15 m/min.

18

Perceptive comparison of mean and full field dynamic recrystallization models

Madej Ł., Sitko M., Pietrzyk M.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 4

569--589

EN

Review of dynamic recrystallization models is the subject of the present work. Development of both mean field and full field approaches during last three decades is presented and discussed. Conventional mean field models based on closed form equations as well as differential equations are presented first. Then full field models are elaborated focusing on the cellular automata approach as an example. Capabilities as well as limitations and drawbacks of these approaches are highlighted based on the set of case studies. Experimental data for validation of models were obtained from uniaxial compression tests at Gleeble 3800 thermo-mechanical simulator.

19

Opracowanie wysokowydajnego systemu do identyfikacji parametrów modelu rekrystalizacji opartego na metodzie automatów komórkowych

Sitko M., Madej Ł.

Rudy i Metale Nieżelazne Recykling

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2015

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R. 60, nr 12

659--663

PL

Celem niniejszej publikacji jest opracowanie i implementacja wysokowydajnego systemu do identyfikacji parametrów modelu rekrystalizacji opartego na metodzie automatów komórkowych z wykorzystaniem podejścia analizy odwrotnej. Założenia algorytmu odwrotnego z uwzględnieniem zastosowanych metod optymalizacji zostały przedstawione w pierwszej części pracy. Następnie opisano wykorzystany w trakcie badań model rekrystalizacji oparty na metodzie automatów komórkowych. Ostania część pracy zawiera wyniki przeprowadzonej identyfikacji oraz ich porównanie z wynikami badań eksperymentalnych.

EN

Subject of this work is development and implementation of high-efficiency system for parameter identification of recrystallization models based on cellular automata method with inverse analysis methods. Main assumption of the inverse algorithm are presented first. Particular attention is put on description of optimization technique used during the research. Then major assumptions of the model of recrystallization based on cellular automata method are provided. Finally, results from model parameters identification procedure realized with the developed approach are presented and compared with experimental results.

20

The effectiveness of recrystallization high carbon steel with regard to the condition of material

Grygier D.

Interdisciplinary Journal of Engineering Sciences

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2015

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Vol. 3, no. 1

20--24

EN

The main aim of the studies presented in paper was to optimize the parameters of the recrystallisation annealing process used in the course of cold plastic working of high carbon steel for patented wires. Object of the research described in the work was eutectoid steel of 0,8% content of C designated for production of colddrawn wires applied for reinforcement of car tires, hoses and ropes. The results of tests show that the condition of the material and mainly degree of plastic deformation has a clearly influence on the effectiveness of pearlitic steel recrystallisation.