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1

Bulk metallic glasses based on magnesium to potential biomedical application

Kiljan A., Nowosielski R.

Selected Engineering Problems

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2015

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nr 6

41--44

EN

The paper presents some informations about materials for biomedical application. The study was performed on ternary Mg-based alloys. The Mg66Zn30Ca4 glassy alloy was prepared in the form of rods by pressure die casting method of molten alloy into water cooled copper mold. This alloy is potential material for biomedical application.

2

Influence of silver on glass forming ability and mechanical properties of Zr–Cu–Al alloys

Błyskun P., Cieślak G., Kowalczyk M., Latuch J., Kulik T.

Inżynieria Materiałowa

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2015

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Vol. 36, nr 4

154--159

EN

The work focuses on studying the influence of silver content on the glass forming ability and the mechanical properties of the Zr48Cu36Al16 – xAgx alloys (x = 0, 2, 4, ..., 16 at. %). Rods with a diameter of 3 mm were manufactured by the copper mould casting. X-ray diffraction studies (Fig. 1) revealed that samples with 6÷14 at. % of silver content were fully amorphous. Differential scanning calorimetry (Fig. 3) allowed selecting the alloy that possessed the best glass forming ability on the basis of the supercooled liquid region width (ΔTx). The Zr48Cu36Al6Ag10 alloy exhibited ΔTx = 91 K. Mechanical properties of the alloys were characterized by means of Vickers microhardness (Fig. 5) and room temperature compression tests (Fig. 6). The highest value of microhardness was detected for the partially crystalline Zr48Cu36Al16 alloy (791 HV). However, the highest compression strength was measured for the Zr48Cu36Al12Ag6 alloy (σc = 1881 MPa). It should be noticed that a plastic strain was observed in the fully amorphous alloys. On the other hand, partially crystalline samples cracked catastrophically without any observable plastic strain. These studies revealed that the silver content increase resulted in the microhardness and the compression strength decrease. Good mechanical performance and satisfying glass forming ability of the fully amorphous alloys examined at this work seems to be promising set of properties for structural applications. However, the Zr48Cu36Al4Ag12 is the most promising one.

PL

Praca dotyczy określenia wpływu dodatku srebra na zdolność do zeszklenia i właściwości mechaniczne stopów Zr48Cu36Al16 – xAgx (x = 0, 2, 4, ..., 16% at.). Pręty o średnicy 3 mm odlewano do formy miedzianej. Badania dyfrakcyjne promieni rentgenowskich wykazały, że próbki o zawartości srebra 6÷14% at. są w pełni amorficzne. Pozostałe stopy miały zbyt małą zdolność do zeszklenia, aby ulec pełnej amorfizacji w formie o średnicy 3 mm. Różnicowa kalorymetria skaningowa pozwoliła wskazać stopy o największej zdolności do zeszklenia wyznaczanej na podstawie szerokości zakresu cieczy przechłodzonej (ΔTx). Stop Zr48Cu36Al6Ag10 cechował się największą zdolnością do zeszklenia ΔTx = 91 K. Właściwości mechaniczne stopów scharakteryzowano za pomocą pomiarów mikrotwardości i statycznej próby ściskania w temperaturze pokojowej. Największszą mikrotwardość zmierzono dla próbki częściowo krystalicznej Zr48Cu36Al16 (791 HV). Jednak największą wytrzymałość na ściskanie uzyskano dla próbki w pełni amorficznej Zr48Cu36Al12Ag6 (σc = 1881 MPa). Należy podkreślić, że dla wszystkich próbek amorficznych odnotowano pewien zakres odkształcenia plastycznego. Natomiast wszystkie próbki częściowo krystaliczne pękały katastroficznie bez odkształcenia plastycznego. Badania wykazały, że wzrost zawartości srebra powoduje zmniejszenie zarówno mikrotwardości, jak i wytrzymałości na ściskanie, ale w pewnym zakresie (6÷15% at.) wyraźnie poprawia zdolność do zeszklenia. Dobre właściwości mechaniczne i zadowalająca zdolność do zeszklenia stopów w pełni amorficznych, badanych w tej pracy, wydają się obiecującym zestawieniem właściwości w przypadku przyszłych zastosowań konstrukcyjnych. Stop o składzie Zr48Cu36Al4Ag12 okazał się optymalnym kandydatem.

3

Fractographic discoveries: investigation of bulk metallic glasses fracture surfaces after static compression test

Błyskun P., Cieślak G., Kowalczyk M., Latuch J., Kulik T.

Inżynieria Materiałowa

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2015

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Vol. 36, nr 2

54--59

EN

The aim of these studies was to broaden the knowledge of bulk metallic glasses failure mechanisms. Two glass forming systems: Zr48Cu36Al16 – xAgx (x = 0, 6, 12, 16 at. %) and Cu48Zr36Ag16 – yTiy (y = 3, 5, 8 at. %) were selected for the studies. Rod shape samples with a diameter of 3 mm were produced from pure elements by the copper mould casting. X-ray diffraction allowed to determine the crystalline phase presence within the samples (Fig. 1). Both partially crystalline and fully amorphous samples were subjected to the static compression tests. The fractography of the resultant scraps was performed by the scanning electron microscopy. The studies reveal several new issues and confirm a few already known related to deformation and fracture mechanisms of metallic glasses. Authors carefully observed and insightfully discussed issues like: main fracture surface exclusiveness for vein-like patterns (Fig. 2), plastic strain implementation by the slip bands proliferation (Fig. 3), vein-like pattern development degree dependence on the fracture stress (Fig. 4), temperature rise relics presence on the main fracture surface (Fig. 5) or determining the origin of a crystalline phase just by the fracture surface observations (Fig. 6, 7). The results presented in this manuscript might be useful for future materials expertise that would potentially be done on metallic glass scraps from failed constructions.

PL

Celem pracy było poszerzenie wiedzy o mechanizmach zniszczenia masywnych szkieł metalicznych. Do badań wybrano dwa układy szkłotwórcze: Zr48Cu36Al16 – xAgx (x = 0, 6, 12, 16 at. %) i Cu48Zr36Ag16 – yTiy (y = 3, 5, 8 at. %). Z czystych pierwiastków wytworzono pręty o średnicy 3 mm metodą odlewania do formy miedzianej. Badania dyfrakcji promieni rentgenowskich pozwoliły ustalić obecność fazy krystalicznej w próbkach. Zarówno próbki częściowo krystaliczne, jak i w pełni amorficzne zostały poddane statycznej próbie ściskania w temperaturze pokojowej. Za pomocą skaningowej mikroskopii elektronowej przeprowadzono obserwacje fraktograficzne otrzymanych przełomów. Badania te umożliwiły potwierdzenie kilku znanych zagadnień oraz odkrycie nowych zjawisk związanych z odkształcaniem i pękaniem szkieł metalicznych. Autorzy dokonali obserwacji oraz omówienia takich kwestii, jak: wyłączność głównej powierzchni pęknięcia na obecność struktury żyłowej, realizowanie odkształcenia plastycznego przez mnożenie pasm poślizgu, zależność stopnia rozwinięcia struktury żyłowej od naprężenia pękania, obecność pozostałości po wzroście temperatury na głównej powierzchni pęknięcia czy określanie pochodzenia fazy krystalicznej na podstawie obserwacji powierzchni pęknięcia. Wyniki przedstawione w pracy mogą być przydatne w przypadku przyszłych ekspertyz materiałowych wykonywanych na złomach elementów konstrukcyjnych ze szkła metalicznego.

4

Structure and Properties of Mg-Cu-(Y,Ca) Bulk Metallic Glasses

Babilas R., Cesarz-Andraczke K., Nowosielski R.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 4

2645--2650

EN

The work presents preparation methods, structure characterization and mechanical properties analysis of Mg-based bulk metallic glasses in as-cast state and after crystallization process. The studies were performed on Mg60Cu30Y10 and Mg37Cu36Ca27 glassy alloys in the form of plates and rods. The X-ray diffraction investigations revealed that the tested samples with different thicknesses and shapes were amorphous. The characteristics of the fractured surfaces showed mixed fractures with the “river” and “mirror” patterns, which are characteristic for the glassy materials and some “smooth” areas. The samples of Mg37Cu36Ca27 alloy presented a two-stage crystallization process, but addition of Y caused a single stage crystallization behavior. Qualitative phase analysis from the X-ray data of examined alloys annealed at 473 K enabled the identification of Mg, Mg2Cu, Cu2Mg and CaCu crystalline phases. The changes of compressive strength as a function of annealing temperature for studied rods were stated. The best mechanical properties including microhardness and compressive strength were obtained for the alloy with the addition of Y in as-cast state.

PL

W pracy przedstawiono wyniki badań struktury i wybranych własności masywnych szkieł metalicznych na osnowie magnezu. Badania przeprowadzono na próbkach w stanie wyjściowym oraz po procesie wygrzewania. Do badań wybrano dwa trójskładnikowe stopy magnezu z dodatkiem itru lub wapnia o następującym składzie chemicznym:Mg60Cu30Y10 oraz Mg37Cu36Ca27. Badania rentgenowskie potwierdziły, że analizowane próbki w postaci płytek i prętów posiadają strukturę amorficzną. Obserwacje mikroskopowe wybranych obszarów powierzchni przełomów płytek i prętów pozwoliły na wyodrębnienie stref o morfologii przełomów „gładkich” i „łuskowych”. Analiza procesu krystalizacji wykazała występowanie pojedynczego etapu krystalizacji dla szkła metalicznego Mg60Cu30Y10 związanego z wydzielaniem się fazy Mg2Cu oraz dwuetapowego procesu krystalizacji dla stopu Mg37Cu36Ca27, w którym zidentyfikowano fazę Cu2Mg i CaCu. Największą wytrzymałość na ściskanie oraz mikrotwardość uzyskano dla próbek szkła metalicznego z dodatkiem itru w stanie bezpośrednio po odlaniu.

5

The production attempt of Fe-Nb-B-Zr and Fe-Nb-B-Y system alloys by die pressure casting method

Pilarczyk W., Kucharczyk M.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 61, nr 2

222-228

EN

Purpose: The purpose of this article was to investigate the possibility of the production of Fe-Nb-B bulk metallic alloys with additions of yttrium and zirconium elements. Furthermore, this paper tends to present the structure and selected properties of obtained alloys. In this article the influence of an argon atmosphere on casting process was observed too. Design/methodology/approach: The production attempts were performed on Fe-Nb-B-Zr and Fe-Nb-B-Y system alloys in form of a plate. Master alloy ingots with compositions of Fe72B22Y4Nb2 and Fe71(Nb0.8Zr0.2)6B23 were prepared by induction melting of pure Fe, Nb, B, Y and Fe, Nb, B, Zr elements in an argon atmosphere. The ingots have been crushed and then the investigated material was cast with and without a protective atmosphere. The investigated materials were cast in form of a plate with thickness of 1 mm. The structure analysis of the studied materials in as-cast state was carried out using X-ray diffraction (XRD) and microscopic observation. The thermal properties of the alloys were examined by DSC methods. The measurments of the hardness were performed with the Vickers method. Findings: The Fe-Nb-B-Y and Fe-Nb-B-Zr system alloys in form of a plate were produced by die pressure casting method. The investigation methods revealed that the studied as-cast alloys were crystalline. The structure of the obtained plates is rather fine-grained and there were not found any impurities and undesirable phases inside the materials. The results of calorimetric curves confirm that all tested samples are crystalline. Practical implications: To extend the potential applications of the Fe-based BMGs, amorphous alloys with larger critical sizes and better processability are required. The Fe-Nb-B-Zr and Fe-Nb-B-Y bulk metallic glasses obtained by die pressure casting method can be used for production of telecommunications devices, sensors or low-energy transformers. These materials exhibit excellent mechanical and soft magnetic properties. Originality/value: An overall presentation of an influence of the yttrium and zirconium additions on the attempt of forming Fe72B22Y4Nb2 and Fe71(Nb0.8Zr0.2)6B23 alloys. The chemical composition of these alloys was tested in our laboratory for the first time.

6

The study of structure and glass forming ability of Zr-based amorphous alloy

Pilarczyk W.

Archives of Materials Science and Engineering

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2013

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Vol. 63, nr 1

19--25

EN

Purpose: This paper tends to present the structure and thermal analysis of selected Zr-based amorphous alloy for welding processes. Design/methodology/approach: The studies were performed on Zr-Cu-Ni-Al system alloy in form of plate. The structure analysis of the studied materials in as-cast state was carried out using XRD method. The thermal properties of the as-cast alloy were examined by DSC and DTA methods. The parameters of GFA included Trg, ΔTx, α, β, γ, δ and S were calculated. Findings: The Zr-based amorphous alloy in form of plate with good GFA was produced by die pressure casting method. The investigation methods revealed that the studied as-cast alloy was amorphous. Although, there is probability of crystallites existence which could not be detected by XRD method. The literature study and calculated GFA parameters indicated that the Zr55Cu30Ni5Al10 alloy exhibits good GFA and thermal stability. It is confirmed that these parameters could be used to determine GFA of tested amorphous alloy for welding processes. This Zr-based BMG could be used as tested material for laser welding process. Research limitations/implications: It is very difficult to obtain a Zr-based BMG with large sizes. Usually, the difficulties of the production of zirconium amorphous alloy are connected with the fact that the constituent elements of the analyzed materials have a high chemical affinity for oxygen, and have different melting points. For this reason, the process of producing BMG in zirconium matrix require the using of additional technology to provide specific conditions for the melting and casting. Practical implications: These obtained values of GFA parameters can suggest that studied alloys are suitable materials for further practical application at welding process. Originality/value: The success formation and investigation of the casted Zr-based BMG. The chemical composition of Zr55Cu30Ni5Al10 alloy was tested first time in our laboratory.

7

Fabrication of Mg65Cu25Y10 bulk metallic glasses

Nowosielski R., Babilas R., Guwer A., Gawlas-Mucha A., Borowski A.

Archives of Materials Science and Engineering

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2012

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Vol. 53, nr 2

77-84

EN

Purpose: The paper describes the preparation, structure and thermal properties of Mg-based bulk metallic glass with chemical composition of Mg65Cu25Y10 in form of as-cast rods. Design/methodology/approach: The investigations on the Mg65Cu25Y10 glassy rods were conducted by using X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) methods. Findings: The X-ray diffraction investigations have revealed that the studied as-cast rod was amorphous. The DSC curve informs about the single stage of crystallization process. The onset crystallization temperature has a value of Tx = 463 K and peak crystallization temperature reaches a value of Tp = 480 K. The fractures of studied alloy could be classified as mixed fracture with indicated “river” and “smooth” fractures. Both type of the fracture surfaces consist of weakly formed “river” and “shell” patterns and “smooth” regions. The “river” patterns are characteristic for metallic glassy alloys. Practical implications: The studied Mg-based bulk metallic glasses are applied for many applications in different elements. Mg-based bulk metallic glasses have much higher tensile strength and Vickers hardness and much lower Young’s modulus in contrast to crystalline magnesium alloys. Magnesium alloys are very attractive for transport and aerospace applications because they are the lightest among the commercially available structural alloys and show excellent damping capacity. Originality/value: Fabrication of amorphous alloy rod Mg65Cu25Y10 by pressure die casting method.

8

A production attempt of selected metallic glasses with Fe and Ni matrix

Pilarczyk W., Nowosielski R., Babilas R.

Archives of Materials Science and Engineering

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2010

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Vol. 41, nr 1

5-12

EN

Purpose: This paper tends to present the microstructure characterization and thermal analysis of the Fe- and Ni-based bulk metallic materials. Design/methodology/approach: The studies were carried out on bulk metallic materials as rods. The rods of the Fe57.6Co7.2Ni7.2B19.2Si4.8Nb4 and Ni64.8Co7.2B19.2Si4.8Nb4 alloys were obtained by the pressure die casting. In order to investigate the structure scanning electron microscopy were used. Phase composition of obtained rods was determined by means of diffractometer. The thermal properties of the studied alloys were examined by differential thermal analysis and differential scanning calorimetry. Findings: The x-ray analysis, microscopic observation and thermal examination revealed that the studied as-cast bulk metallic materials were of amorphous, crystalline and mixed structure. Broad diffraction halo can be seen for rods with diameter of ø=1.5 and 2mm of Fe57.6Co7.2Ni7.2B19.2Si4.8Nb4 alloy. The replacement of Fe by Ni created crystalline structure. Practical implications: Fe- and Ni-based bulk metallic glass systems have been developed because they offer great potential for commercial application. Fe-based ferromagnetic bulk glassy alloys exhibit great magnetic properties. It is very important for their magnetic applications. That alloys can be used as soft electro-magnetic cores for choke coil or noise filter. Ni-based bulk metallic glasses exhibit excellent mechanical properties and corrosion resistance. Originality/value: The formation and studies of the casted Fe- and Ni-based bulk materials and investigation of the effectiveness of the replacement of Fe by Ni.

9

Structure and soft magnetic properties of Fe72B20Si4Nb4 bulk metallic glasses

Nowosielski R., Babilas R., Griner S., Stokłosa Z.

Archives of Materials Science and Engineering

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2009

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Vol. 35, nr 1

13-20

EN

Purpose: The paper presents a microstructure characterization, thermal stability and soft magnetic properties analysis of Fe-based bulk amorphous materials. Design/methodology/approach: The studies were performed on Fe₇ ₂B₂ ₀Si₄Nb₄ glassy alloy in form of ribbons and rods. The amorphous structure of tested samples was examined by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) methods. The thermal properties of the glassy samples were measured using differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The magnetic properties were determined by the Maxwell-Wien bridge and VSM methods. Findings: The X-ray diffraction and transmission electron microscopy investigations have revealed that the studied as-cast bulk metallic glasses were amorphous. Broad diffraction halo can be seen for all tested samples, indicating the formation of a glassy phase with the diameters up to 2 mm. The fracture surface of rod samples appears to consist of small fracture zones, which leads to breaking of the samples into parts. A two stage crystallization process was observed for studied amorphous alloy. The changes of crystallization temperatures and magnetic properties as a function of glassy samples thickness were stated. Practical implications: The studied Fe-based alloy system has good glass-forming ability and thermal stability for casting bulk metallic glasses, which exhibit good soft magnetic properties, useful for many electric and magnetic applications. Originality/value: The obtained examination results confirm the utility of applied investigation methods in the microstructure, thermal and soft magnetic properties analysis of examined bulk amorphous alloys.

10

Fabrication of bulk metallic glasses by centrifugal casting method

Nowosielski R., Babilas R.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

487-490

EN

Purpose: The aim of the present work is characterization of the centrifugal casting method, apparatus and produced amorphous materials, which are also known as bulk metallic glasses. Design/methodology/approach: The studied centrifugal casting system consists of two main parts: casting apparatus and injection system of molten alloy. The described centrifugal casting method was presented by preparing a casting apparatus "CentriCast - 5". The apparatus includes a cylindrical copper mold, which is rotated by a motor. The transmission allows to changing the speed of rotating mold. Findings: Bulk metallic glasses are a novel class of engineering materials, which exhibit excelent mechanical, thermal, magnetic and corrosion properties. Centrifugal casting is a useful method to produce bulk amorphous materials in form of rings, tubes or cylindrical parts. Presented centrifugal casting method and casting apparatus has been prepared to fabricate the samples of bulk metallic glass in form of rings with an outer diameter of 25 mm and controlled thicknesses by changing the weight of the molten alloy. Research limitations/implications: Studied centrifugal casting method and casting apparatus has been prepared to fabricate the samples of bulk metallic glass. For future research a characterization of microstructure and properties of prepared material will be performed. Practical implications: The centrifugal casting is a useful process to produce bulk amorphous materials in form of rings, tubes or graded amorphous matrix composites. It seems to be a very simple method, which allows to obtain BMG materials. Originality/value: The centrifugal casting method allows to produce bulk amorphous rings with thickness above 1-mm.

11

Selection rules for the production of bulk metallic glass precursors for shape memory materials

Kolomytsev V., Pasko A., Sezonenko A.

Archives of Metallurgy and Materials

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2004

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Vol. 49, iss. 4

825-840

EN

The paper is focused on the development of the following technological paths: (metallic melt) › (bulk metallic glass precursor of shape memory material) › (superplastic deformation on heating through the supercooled liquid region) › (crystallization and final microcrystalline material with martensitic transformation in a predetermined temperature range). Main attention is paid to design of multicomponent (Ti,Zr,Hf)A(Co,Ni,Cu,Pd) B alloys with compositions varied around an effective intermetallic compound AB (A:B = 45:55; 50:50; 55:45). One of the challenging problems here is to find a chemical composition window of our multicomponent systems fitting the known empirical rules for a high amorphization ability and keeping the martensitic transformation and good shape memory properties after crystallization.

PL

Artykuł przedstawia rozwój następującej ściezki technologicznej: (ciecz metaliczna) - (masywne szkło metaliczne jako prekursor materiału z pamięcią kształtu) - (nadplastyczne odkształcenie w zakresie cieczy przechłodzonej) - (krystalizacja w określonym zakresie temperatur i uzyskanie końcowego mikrokrystalicznego materiału z przemiana martenzytyczną). Główną uwagę zwrócono na zaplanowanie wieloskładnikowych stopów (Ti, Zr, Hf)A(Co, Ni, Cu, Pd)B o składzie zmieniajacym się w poblizu składu związku międzymetalicznego AB. Jednym z podstawowych problemów jest znalezienie zakresu składów chemicznych dla układów wieloskładnikowych, pasujących do znanych regułempirycznych tworzenia stopów o dużej zdolności do amorfizacji, i równocześnie zachowania przemiany martenzytycznej oraz dobrego efektu pamięci kształtu po krystalizacji.