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1

Influence of Milling Time on Formation of NiTi Alloy Produced by High-Energy Ball Milling

Salwa P., Goryczka T.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 3

1017--1022

EN

Mixture of nickel and titanium powders were milled in planetary mill under argon atmosphere for 100 hours at room temperature. Every 10 hours the structure, morphology and chemical composition was studied by X-ray diffraction method (XRD), scanning electron microscope (SEM) as well as electron transmission microscope (TEM). Analysis revealed that elongation of milling time caused alloying of the elements. After 100 hours of milling the powders was in nanocrystalline and an amorphous state. Also extending of milling time affected the crystal size and microstrains of the alloying elements as well as the newly formed alloy. Crystallization of amorphous alloys proceeds above 600°C. In consequence, the alloy (at room temperature) consisted of mixture of the B2 parent phase and a small amount of the B19' martensite. Dependently on the milling time and followed crystallization the NiTi alloy can be received in a form of the powder with average crystallite size from 1,5 up to 4 nm.

2

Influence of Milling Time on Formation of NiTi Alloy Produced by High-Energy Ball Milling

Salwa P., Goryczka T.

Archives of Metallurgy and Materials

|

2019

|

Vol. 64, iss. 4

1301--1307

EN

Mixture of nickel and titanium powders were milled in planetary mill under argon atmosphere for 100 hours at room temperature. Every 10 hours the structure, morphology and chemical composition was studied by X-ray diffraction method (XRD), scanning electron microscope (SEM) as well as electron transmission microscope (TEM). Analysis revealed that elongation of milling time caused alloying of the elements. After 100 hours of milling the powders was in nanocrystalline and an amorphous state. Also extending of milling time affected the crystal size and microstrains of the alloying elements as well as the newly formed alloy. Crystallization of amorphous alloys proceeds above 600°C. In consequence, the alloy (at room temperature) consisted of mixture of the B2 parent phase and a small amount of the B19’ martensite. Dependently on the milling time and followed crystallization the NiTi alloy can be received in a form of the powder with average crystallite size from 1,5 up to 4 nm.

3

The Effect of Additive Element on the Properties of Mechanically Alloyed Fe-Y2O3 Alloys

Ahn J.-H., Kim T. K., Ahn J.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1043--1046

EN

In the present work, we have examined the effect of Ti on the properties of Fe-Y2O3 alloys. The result showed that the addition of Ti was effective for improving mechanical properties. This is due to the reduction of oxides by Ti during mechanical alloying and hot-consolidation. In particular, iron oxides are effectively reduced by the addition of Ti. Compared to the pristine Fe-Y2O3 alloys, titanium-added alloys exhibited fine and uniform microstructures, resulting in at least 60% higher tensile strength.

4

Modyfication of photocatalytic properties of titanium dioxide by mechanochemical method

Dulian P., Buras M., Żukowski W.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 3

68--71

EN

The paper presents a simple way to improve the photocatalytic properties of titanium dioxide using mechanochemical method. The TiO2 (Anatase) powders was subjected to high-energy ball milling in dry environment and in methanol. It has been shown that it is possible to induce the phase transformation from Anatase to Rutile and produce a material with a higher photocatalytic activity in the UV light. Physicochemical characteristics of the products were based on the following methods and techniques: X-ray powder diffraction (XRD), IR and UV-Vis (DR) spectroscopy, measurements of specific surface area (BET). The photocatalytic activity of the powders was measured in the decomposition reaction of methyl orange in water.

5

Effect Of Different Mechanical Milling Processes On Morphology And Microstructural Changes Of Nano And Micron Al-Powders

Kim H.-S., Madavali B., Eom T.-J., Kim C.- M., Koo J.-M., Lee T. H., Hong S.-J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1235--1239

EN

In this research, effect of the various mechanical milling process on morphology and microstructural changes of nano and micron Al-powders was studied. The milling of Al-powders was performed by both high energy and low energy ball milling process. The influence of milling (pulverizing) energy on the structural changes of Al-powders was studied. Al-nanoparticles were agglomerated during the MA and its size was increased with increasing milling while micron Al-powder gets flattened shape during high energy ball milling due to severe plastic deformation. Meanwhile, structural evolution during high energy ball milling of the nano powder occurred faster than that of the micron powder. A slight shift in the position of X-ray diffraction peaks was observed in nano Al-powders but it was un-altered in macro Al-powders. The variation in lattice parameters was observed only for nano Al powders during the high energy ball milling due to lattice distortion.

6

Wpływ wysokoenergetycznego mielenia na parametry eksploatacyjne materiału katodowego stosowanego w ogniwach cynkowo-węglowych

Skowroński J. M., Osińska M., Rozmanowski T., Rogulski Z.

Przemysł Chemiczny

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2014

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T. 93, nr 5

701-703

PL

Przeprowadzono badania elektrochemiczne, z zastosowaniem metody woltamperometrii cyklicznej oraz pomiarów galwanostatycznych masy czarnej pochodzącej z recyklingu zużytych ogniw cynkowo-węglowych. Wykazano, że proces wysokoenergetycznego mielenia wpływa na mechanizm reakcji oraz poprawia kinetykę procesu i pojemność rozładowania badanych mieszanek katodowych. Na podstawie wyników uzyskanych w trakcie rozładowania badanych materiałów prądem o stałych gęstościach wynoszących 10 i 25 mA/g stwierdzono, że optymalny czas mielenia wynosi 3 h.

EN

The black mass recycled from waste Zn-C cells was high-energy ball milled to study mechanism and improve the kinetics and discharge capacity of cathode mixts. The optimum milling time was 3 h according to measurements carried out at const. c. d. 10 and 25 mA/g.

7

Polepszenie pojemności rozładowania materiału katodowego stosowanego w ogniwach cynkowo-węglowych w wyniku wysokoenergetycznego mielenia z dodatkiem ekspandowanego grafitu

Skowroński J. M., Osińska M., Rozmanowski T., Rogulski Z.

Przemysł Chemiczny

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2014

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T. 93, nr 5

697-700

PL

Przeprowadzono badania elektrochemiczne z zastosowaniem metody galwanostatycznej. Wykazano, że proces wysokoenergetycznego mielenia masy czarnej pochodzącej z recyklingu zużytych ogniw cynkowo-węglowych z dodatkiem ekspandowanego grafitu przyczynia się do wzrostu pojemności rozładowania badanych mieszanek katodowych. Na podstawie wyników uzyskanych w trakcie rozładowania badanych materiałów prądem o stałych gęstościach wynoszących 10 i 25 mA/g stwierdzono, że pojemność właściwa wzrasta wraz z wydłużaniem czasu mielenia.

EN

The black mass recycled from waste Zn-C cells and admixed with expanded graphite was high-energy ball milled to improve the discharge capacity of cathode mixts. The capacity increased along with time of milling according to the measurements carried out at const. c. d. 10 and 25 mA/g.

8

Dielectric properties of vanadium doped barium titanate synthesized via high-energy ball milling

Dulian P., Bąk W., Wieczorek-Ciurowa K., Kajtoch C.

Materials Science Poland

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2014

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Vol. 32, No. 2

257--263

EN

The study shows the advisability of using a mechanochemical synthesis method, based on a high-energy planetary ball milling, to a modification of barium titanate by a vanadium doping. This method improves useful properties of BaTi0:95V0:05O3 as a capacitor material. It has a high value of electric permittivity e' in the wide range of temperature and low dielectric losses e" as well as a low electrical conductivity.

9

Controlled mechanochemical synthesis and properties of a selected perovskite-type electroceramics

Dulian P., Bąk W., Wieczorek-Ciurowa K., Kajtoch C.

Materials Science Poland

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2013

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Vol. 31, No. 3

462--470

EN

This paper presents mechanochemical synthesis as an alternative to the traditional high-temperature synthesis of advanced electrotechnical ceramic materials with a perovskite-type structure. The reaction conditions for high-energy ball milling, e.g. reaction environment, energy of milling and additives to BaTiO3 such as metallic iron or zirconia from the exfoliation of the milling vessel and grinding media are discussed.

10

The Influence of Manufacturing Conditions on Microstructure and Magnetic Properties of BaFe12O19 Powders

Dercz G., Babilas R., Nowosielski R., Pająk L.

Archives of Metallurgy and Materials

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2010

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Vol. 55, iss. 1

181-185

EN

The aim of the paper was a trial of using mechanical alloying process of mixture iron oxide and barium carbonate to produce BaFei2Oi9 powders. The milling process was carried out in a vibratory mili for 10, 20 and 30 hours. The size distributions of powder particles showed that the size of tested particles increases with the increase of milling time indicating the agglomeration process of particles. The milling process of Fe203 and BaC03 mixture for studied milling times causes decrease of the crystallite size of involved phases and leads to increase of Fe203 phase content and decrease of BaC03 one. The milling process did not lead to formation of BaFei2Oi9 phase, thus it probably causes setting of Fe203 on surface layer of BaC03 powder particles. The XRD investigations of Fe203 and BaC03 mixture milled for 10, 20 and 30 hours and annealed at 1000°C for 1 hour enabled the identification of hard magnetic BaFei2Oi9 phase. For applied magnetic field of 800 kA/m, the coercive force is eąual to 343 kA/m, 358 kA/m and 366 kA/m whereas the remanence is eąual to 0.118 T, 0.109 T and 0.127 T for the samples after milling for 10, 20 and 30 hours, respectively.

PL

Celem pracy była próba wykorzystania procesu mechanicznej syntezy mieszaniny tlenku żelaza (Fe203) i węglanu baru (BaC03) do wytworzenia proszków BaFei2Oi9. Proces mielenia przeprowadzono w młynie wibracyjnym w czasie 10, 20 oraz 30 godzin. Rozkłady wielkości cząstek proszków wykazały, że wielkość cząstek wzrasta ze wzrostem czasu mielenia wskazując, że w trakcie procesu mielenia następuje proces aglomeracji cząstek. Proces mielenia mieszaniny Fe203 i BaC03 dla zastosowanych czasów prowadzi do zmniejszenia wielkości krystalitów tych faz oraz do wzrostu udziału fazy Fe203 i spadku udziału fazy BaC03. Mielenie mieszaniny Fe203 i BaC03 w czasie 10, 20 i 30 godzin z następnym wyżarzaniem w 1000°C w czasie 1 godziny, prowadzi do powstania fazy magnetycznie twardej BaFei2Oi9. Dla przyłożonego pola magnetycznego 800 kA/m najwyższą wartość koercji i remanencji uzyskano dla próbki mielonej w czasie 30 godzin i wyżarzanej w 1000°C, odpowiednio 366 kA/m i 0,127 T.

11

Microstructure and magnetic properties of BaFe12O19 powder

Nowosielski R., Babilas R., Dercz G., Pająk L., Skowroński W.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 27, nr 1

51-54

EN

Purpose: Analysis of microstructure and magnetic properties of BaFe12O19 powder obtained by milling and annealing of Fe2O3 and BaCO3 precursors. Design/methodology/approach: The mixture of iron oxide (Fe2O3) and barium carbonate (BaCO3) powders was used to obtain BaFe12O19 powder by using high-energy ball milling and heat treatment processes. The X-ray diffraction methods were used for qualitative, quantitative phase analyses and for crystallite size and lattice distortion determination. The thermal properties of the studied powders were analyzed using the differential thermal analysis (DTA). The magnetic properties of examined powder material were studied by resonance vibrating sample magnetometer (R-VSM). The size of powder particles was determined by a laser particle analyzer. Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases. The X-ray diffraction investigations of Fe2O3 and BaCO3 mixture milled for 50 hours and annealed at 850, 900, 950 and 1000*C enabled the identification of hard magnetic BaFe12O19 phase and also small amount of Fe2O3 phase. The magnetic properties of studied powders are dependent on temperature of their annealing. The sample annealed at 1000*C has the best hard magnetic properties from all studied samples. The content changes of hard magnetic phase (BaFe12O19) with the increase of annealing temperature results in the improvement of hard magnetic properties. Practical implications: The BaFe12O19 powder can be suitable component to produce sintered hard magnetic materials. Originality/value: The study results of BaFe12O19 powders confirm the utility of applied investigation methods in the microstructure and magnetic properties analysis of powder materials.

12

Microstructure investigations of Co-Si-B alloy after milling and annealing

Nowosielski R., Babilas R., Dercz G., Pająk L.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 23, nr 1

59-62

EN

Purpose: The work presents the microstructure characterization of Co77Si11,5B11,5 metallic glass after high-energy ball milling and heat treatment processes. Design/methodology/approach: The studies were performed on ribbon prepared by melt spinning and this ground in high-energy vibratory ball mill. The tested ribbon and obtained powders were also annealed in specified heat treatment conditions. The morphology of the powder particles of milled ribbon was analyzed by using the confocal laser scanning microscope. The methods of X-ray diffraction were used for the qualitative phase analysis. The parameters of the individual diffraction line profiles were determined by PRO-FIT Toraya procedure. The average crystallite sizes and lattice distortions for Co phase were estimated using Williamson-Hall method. Findings: The studied Co77Si11,5B11,5 metallic glass in annealed state contains hexagonal Co crystalline phases emerged in amorphous matrix. The crystallite size of Co phase in as-cast sample lies in nanoscale. After annealing process the crystallite size increases to 72 nm and diminishes to 46 nm in the powder sample after 30 hours of milling. The milling causes decrease of the crystallite size and increase of lattice distortions of crystalline phase. The powder particles after 30 hours of milling are of spherical shape. Practical implications: The powder particles obtained after milling process of Co-based metallic glass could be suitable components in production of ferromagnetic nanocomposites. Originality/value: The obtained results confirm the utility of applied investigation methods in the microstructure analysis of powder materials with nanocrystalline phases.

13

Barium ferrite powders prepared by milling and annealing

Nowosielski R., Babilas R., Dercz G., Pająk L., Wrona J.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 22, nr 1

45-48

EN

Purpose: Microstructure and magnetic properties analysis of barium ferrite powder obtained by milling and heat treatment. Design/methodology/approach: the milling process was carried out in a vibratory mill, which generated vibrations of the balls and milled material in side the container during which their collisions occur. After milling process the powders were annealed in electric chamber furnace. The X-ray diffraction methods were used for qualitative phase analysis of studied powder samples. The distribution of powder particles was determined by a laser particle analyser. The magnetic hysteresis loops of examined powder material were measured by resonance vibrating sample magnetometer (R-VSM). Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases. The X-ray investigations of tested mixture milled for 30 hours and annealed at 950 degrees centigrade enabled the identification of hard magnetic BaFe12O19 phase and also the presence of Fe2O3 phase in examined material. The Fe2O3 phase is a rest of BaCO3 dissociation in the presence of Fe2O3, which forms a compound of BaFe12O19. The best coercive force (HC) for mixture of powders annealed at 950 degrees centigrade for 10,20 and 30 hours is 349 kA/m, 366 kA/m and 364 kA/m, respectively. The arithmetic mean of diameter of Fe2O3 and BaCO3 mixture powders after 30 hours of milling is about 6.0 micrometres. Practical implications: The barium ferrite powder obtained by milling and annealing can be suitable components to produce sintered and elastic magnets with polymer matrix. Originality/value: The results of tested barium ferrite investigations by different methods confirm their utility in the microstructure and magnetic properties analysis of powder materials.

14

Structure and properties of barium ferrite powders prepared by milling and annealing

Nowosielski R., Babilas R., Dercz G., Pająk L., Wrona J.

Archives of Materials Science and Engineering

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2007

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Vol. 28, nr 12

735-742

EN

Purpose: Microstructure and magnetic properties analysis of barium ferrite powder obtained by milling and heat treatment Design/methodology/approach: The milling process was carried out in a vibratory mill, which generated vibrations of the balls and milled material inside the container. After milling process the powders were annealed in electric chamber furnace. The X-ray diffraction methods were used for qualitative phase analysis of studied powder samples. The morphology of Fe2O3 and BaCO3 powders after milling was analyzed using the scanning electron microscopy (SEM) method. The distribution of powder particles was determined by a laser particle analyzer. The magnetic hysteresis loops of examined powder material were measured by resonance vibrating sample magnetometer (R-VSM). Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases and leads to increase the content of Fe2O3 phase and decrease of BaCO3 content. Milling process causes enriching of surface layer of powder particles by Fe2O3. The X-ray investigations of tested mixture milled for 30 hours and annealed at 950*C enabled the identification of hard magnetic BaFe12O19 phase and also the presence of Fe2O3 phase in examined material. The Fe2O3 phase is a rest of BaCO3 dissociation in the presence of Fe2O3, which forms a compound of BaFe12O19. The best coercive force for the mixture of powders annealed at 950oC for 10, 20 and 30 hours is 349 kA/m, 366 kA/m and 364 kA/m, respectively. From morphology images and distribution of powder particle size it can be concluded, that the size of tested powder particles increases with increasing time of milling process. The increase of milling time up to 20 hours leads to joining of smaller particles in bigger ones; agglomerates are formed. Practical implications: The barium ferrite powder obtained by milling and annealing can be suitable component to produce sintered and elastic magnets with polymer matrix. Originality/value: The results of tested barium ferrite investigations by different methods confirm their utility in the microstructure and magnetic properties analysis of powder materials.

15

Mechanochemical synthesis of nanocrystalline cermets

Wieczorek-Ciurowa K., Gamrat K.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 3

51-53

EN

The formation of cermet consisting of Cu(Al) solid solution and aluminium oxide was discussed. The composite synthesized by high-energy ball milling carried out in a laboratory planetary mill. Salt and active metal, Cu-hydroxycarbonate and powdered aluminium, were used as the starting materials. Phase analysis of the mechanochemically synthesized product was carried out on the basis of X-ray diffractometry and thermal analysis methods.

16

Structural and morphological changes in copper hydroxocarbonate-1 aluminium system induced by mechanical activation

Wieczorek-Ciurowa K., Gamrat K., Fela K., Sawłowicz Z.

Polish Journal of Chemical Technology

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2003

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Vol. 5, nr 3

72-74

EN

The copper hydroxocarbonate with Al mixture was mechanically activated (MA) using a planetary ball mill and the products were examined by scanning electron microscopy (SEM) with energy dispersive X-ray microanalysis (EDX). Backscattered electron (BSE) imaging was used to localize the alloy phases formed as a result of mechanochemical reactions. These information were compared with thermal analysis and powder X-ray diffraction studies.

17

Rozdrobnienie struktury w wyniku mechanicznego mielenia ferrytu baru.

Ławecka M., Leonowicz M.

Archiwum Nauki o Materiałach

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2001

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T. 22, nr 3

191-201

PL

Przeprowadzono badania procesu rozdrabniania struktury ferrytów baru w trakcie ich długotrwałego mechanicznego mielenia w młynie kulowym. Stwierdzono, że wielkość cząstek proszku zmniejsza się od wartości 340 nm dla materiału wyjściowego do 50 nm dla czasów mielenia dłuższych niż 100 h, po czym pozostaje stała. Wielkość krystalitów jest zbliżona do wielkości cząstek proszku. Jednak dla długich czasów przemiału, rzędu 200 h, zaczyna odbiegać od wielkości cząstek, a struktura ulega zdefektowaniu, co przejawia się w utracie własności typowych dla materiału magnetycznie twardego i w zdolności cząstek do orientacji w polu magnetycznym.

EN

Studies of structure refinement, in the course of high-energy ball milling, were performed for barium ferrite material. It has been found that the powder particle size decreases from 340 nm, for the as supplied powder, down to 50 nm for milling times longer than 100 h, thereafter settles down at the level of 50 nm. The crystallite size follows the particle size, however, for milling times longer than 200 h the gap between these two parameters becomes wider. This leads to the loss of permanent magnet properties as well as the ability of particle alignment in a magnetic field.