Structural, Magnetic and Crystallization Study of Fe-Based Bulk Metallic Glasses

The work presents the structural, thermal and magnetic properties analysis of Fe72B20Si4Nb4 bulk metallic glasses in as-cast state and crystallization study of bulk amorphous alloy after annealing process. The studies were performed on bulk metallic glasses in of rods form with diameter of 1,5 and 2 mm. The structure analysis of the samples in as-cast state and phase analysis of studied alloy after annealing process was carried out by the X-ray diffraction (XRD) methods. Mössbauer spectroscopy (MS) was also used to investigate the local structure for studied bulk metallic glasses. Thermal properties associated with glass transition, onset and peak crystallization temperatures was examined by differential scanning calorimetry (DSC). The soft magnetic properties examination of tested material contained initial magnetic permeability and disaccommodation of magnetic permeability.

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An Investigation Into The Effect Of Isothermal Annealing On Magnetic Properties In The Alloy: Fe64Co10Y6B20

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0337 ◽

2015 ◽

Vol 60 (3) ◽

pp. 1987-1992

Author(s):

M. Nabiałek

Keyword(s):

Magnetic Properties ◽

Isothermal Annealing ◽

Structural Defects ◽

Bulk Amorphous Alloy ◽

Cast State ◽

Soft Magnetic ◽

Scanning Calorimetry ◽

Saturation Magnetisation ◽

Crystallisation Temperature ◽

Saturation Theorem

AbstractThis work presents the results of investigations into the structural and magnetic properties of the bulk amorphous alloy: Fe64Co10Y6B20. The structure, thermal stability and magnetic properties of the alloy were studied using: X-ray diffractometry, differential scanning calorimetry (DSC), and a vibrating sample magnetometer (VSM), respectively. The investigations were performed on samples of the alloy in both the ‘as-cast’ state, and the state resulting from a process of isothermal annealing at a temperature of 750 K for 30 minutes.The aim of the conducted studies was to relax the structure and improve the soft magnetic properties of the investigated alloy. The results show that annealing the alloy at a temperature well below its crystallisation temperature leads to an increase in the value of the saturation magnetisation and a decrease in the value of the coercivity. Utilising the ‘approach to the ferromagnetic saturation’ theorem, the nature of structural defects within the investigated material has been established. For both ‘as-cast’ and isothermally-annealed samples, the magnetisation process has been found to be connected with the existence of linear structural defects.

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Plasticity of bulk metallic glasses improved by controlling the solidification condition

Journal of Materials Research ◽

10.1557/jmr.2008.0127 ◽

2008 ◽

Vol 23 (4) ◽

pp. 941-948 ◽

Cited By ~ 40

Author(s):

Z.W. Zhu ◽

S.J. Zheng ◽

H.F. Zhang ◽

B.Z. Ding ◽

Z.Q. Hu ◽

...

Keyword(s):

Metallic Glasses ◽

Bulk Metallic Glasses ◽

High Energy ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Solidification Condition ◽

X Ray ◽

Transmission Electron ◽

Injection Casting

Different bulk metallic glasses (BMGs) were prepared in ductile Cu47.5Zr47.5Al5, Zr62Cu15.4Ni12.6Al10, and brittle Zr55Ni5Al10Cu30 alloys by controlling solidification conditions. The achieved microstructures were characterized by x-ray diffraction, differential scanning calorimetry, transmission electron microscopy, and synchrotron- based high-energy x-ray diffraction. Monolithic BMGs obtained by high-temperature injection casting are brittle, while BMGs bearing some nanocrystals with the size of 3 to 7 nm and 2 to 4 nm, obtained by low-temperature injection casting and in situ suction casting, respectively, exhibit good plasticity. It indicates that the microstructures of BMGs are closely affected by the solidification conditions. Controlling the solidification conditions could improve the plasticity of BMGs.

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Copper Based Bulk Metallic Glasses for Medical Devices

Materiale Plastice ◽

10.37358/mp.19.4.5256 ◽

2019 ◽

Vol 56 (4) ◽

pp. 700-704

Author(s):

Carmen Opris ◽

Cosmin Codrean ◽

Dragos Buzdugan ◽

Petru Hididis

Keyword(s):

Medical Devices ◽

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Chemical Compositions ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Copper Mold Casting ◽

Mold Casting ◽

Materials Used

Bulk metallic glasses (BMGs) represent a viable alternative for replacing classic materials used in medical devices. This paper presents the research conducted in order to obtain copper based BMGs using two different chemical compositions: Cu48Zr47Al5 and Cu45Zr45Al5Ag5. The samples were obtained by copper mold casting and their structure and properties were investigated using X-Ray diffraction (XRD), differential scanning calorimetry (DSC) and optical microscopy.

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Microstructures and Synthesis of Noble Metal-Based Bulk Metallic Glasses (Zr-Be-Ni-Ti)

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.17.1 ◽

2016 ◽

Vol 17 ◽

pp. 1-6

Author(s):

M. Abo-Elsoud

Keyword(s):

Metallic Glasses ◽

Thermal Analyses ◽

Bulk Metallic Glasses ◽

High Energy ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Stage Crystallization ◽

Energy Ball ◽

Experimental Findings

High-energy ball-milling in hexane medium was employed to prepare Nobel Zr-based bulk metallic glasses (BMGs) alloy of three different nominal compositions Zr47Be23Ni15Ti15, Zr50Be20Ni15Ti15 and Zr52Be18Ni15Ti15, numbers indicate at.%). The glass forming ability was found to increase with decreasing Zr and increasing Be content, which can be ascribed to the enhanced atomic size mismatch of the constituents on Be addition. Amorphous Zr47Be23Ni15Ti15 powder undergoes two-stage crystallization with onset temperatures at 640 and 700 K and glass transition temperature Tg at 566 K. In contrast, the Zr50Be20Ni15Ti15 and Zr52Be18Ni15Ti15 samples remained crystalline to a certain extent even after prolonged milling and contained FCC Zr crystallites. Structural characterization was done by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, thermal analyses were performed by means of differential scanning calorimetry (DSC) thermogram to justify the experimental findings.

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Magnetic properties optimization of Zr/Fe dual amorphous phase bulk metallic glasses

Revista UIS Ingenierías ◽

10.18273/revuin.v19n1-2020006 ◽

2020 ◽

Vol 19 (1) ◽

pp. 67-71

Author(s):

Mircea Vodă ◽

Cosmin Codrean ◽

Viorel Aurel Şerban ◽

Dacian Toṣa ◽

Eugen Zặbavặ ◽

...

Keyword(s):

Magnetic Properties ◽

Amorphous Phase ◽

Metallic Glasses ◽

Amorphous Alloys ◽

Glassy Alloy ◽

Bulk Metallic Glasses ◽

Volume Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Viable Method

The dual amorphous phase bulk metallic glasses (DAPBMGs) contain two distinct amorphous alloys in order to bring together all the favorable properties of each phase. A viable method for obtaining dual bulk amorphous alloys is powder metallurgy. A Zr/Fe DAPBMG were successfully prepared by hot-pressing of Zr –based and Fe –based glassy alloy powder in different volumetric proportions. The samples obtained were structural investigated by scanning electron microscopy and X-Ray diffraction. Magnetic properties were determined using hysteresis graph of integrator fluxmeter type. It was found that with increasing the volume ratio of the Fe-based alloy decreases the coercivity and increases saturation magnetization

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Inverse Design of Fe-Based Bulk Metallic Glasses Using Machine Learning

Metals ◽

10.3390/met11050729 ◽

2021 ◽

Vol 11 (5) ◽

pp. 729

Author(s):

Junhyub Jeon ◽

Namhyuk Seo ◽

Hwi-Jun Kim ◽

Min-Ha Lee ◽

Hyun-Kyu Lim ◽

...

Keyword(s):

Thermal Properties ◽

Metallic Glasses ◽

Alloy Composition ◽

Relevant Literature ◽

Bulk Metallic Glasses ◽

X Ray Diffraction ◽

X Ray ◽

Ann Models ◽

Wide Scale ◽

Artificial Neural Network Ann

Fe-based bulk metallic glasses (BMGs) are a unique class of materials that are attracting attention in a wide variety of applications owing to their physical properties. Several studies have investigated and designed the relationships between alloy composition and thermal properties of BMGs using an artificial neural network (ANN). The limitation of the wide-scale use of these models is that the required composition is yet to be found despite numerous case studies. To address this issue, we trained an ANN to design Fe-based BMGs that predict the thermal properties. Models were trained using only the composition of the alloy as input and were created from a database of more than 150 experimental data of Fe-based BMGs from relevant literature. We adopted these ANN models to design BMGs with thermal properties to satisfy the intended purpose using particle swarm optimization. A melt spinner was employed to fabricate the designed alloys. X-ray diffraction and differential thermal analysis tests were used to evaluate the specimens.

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A Conflict of Fineness and Stability: Platinum- and Palladium-Based Bulk Metallic Glasses for Jewellery

Johnson Matthey Technology Review ◽

10.1595/205651321x16045078967011 ◽

2020 ◽

Author(s):

O. S. Houghton ◽

A. L. Greer

Keyword(s):

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Precious Metals ◽

High Hardness ◽

Scratch Resistance ◽

Cast State ◽

High Definition ◽

Glass Forming ◽

Thermoplastic Forming ◽

Near Net Shape

For the metals used in jewellery, high hardness and the associated scratch resistance are much sought after. Conventional crystalline alloys for jewellery are alloyed and extensively processed (thermally and mechanically) to improve hardness, but it is difficult to reach values beyond 300 HV. The advent of bulk metallic glasses, based on precious metals and with hardness exceeding 300 HV in the as-cast state, is therefore of great interest for both jewellery and watchmaking. The non-crystalline structure of these materials not only gives high hardness, but also the opportunity to shape metals like plastics, via thermoplastic forming. For more traditional jewellery manufacture, bulk metallic glasses also exhibit high-definition and near-net-shape casting. Gold-based alloys have long dominated the consideration of bulk metallic glasses for jewellery as they can comply with 18K hallmarks. Although bulk metallic glasses based on platinum or palladium possess excellent thermoplastic formability, and are without known tarnishing problems, achieving useful glass-forming ability within the more restrictive hallmarking standards typically used for jewellery (≥95 wt.% Pt or Pd) is, at best, challenging. In this review, platinum- and palladium-based bulk metallic glasses are discussed, focusing on their potential application in jewellery and on the further research that is necessary.

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The effect of structural changes during sintering on the electric and magnetic traits of the Ni96.7Mo3.3 alloy nanostructured powder

Science of Sintering ◽

10.2298/sos0902175r ◽

2009 ◽

Vol 41 (2) ◽

pp. 175-184 ◽

Cited By ~ 7

Author(s):

L. Ribic-Zelenovic ◽

M. Spasojevic ◽

A. Maricic ◽

M.M. Ristic

Keyword(s):

Electrical Resistivity ◽

Magnetic Permeability ◽

Structural Relaxation ◽

Crystalline Phase ◽

Structural Changes ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Fcc Lattice ◽

Lower Permeability ◽

Structural Powder

Ni96.7Mo3.3 powder was electrochemically obtained. An X-ray diffraction analysis determined that the powder consisted of a 20% amorphous and 80% crystalline phase. The crystalline phase consisted of a nanocrystalline solid nickel and molybdenum solution with a face-centred cubic (FCC) lattice with a high density of chaotically distributed dislocations and high microstrain value. The scanning electronic microscopy (SEM) showed that two particle structures were formed: larger cauliflower-like particles and smaller dendriteshaped ones. The thermal stability of the alloy was examined by differential scanning calorimetry (DSC) and by measuring the temperature dependence of the electrical resistivity and magnetic permeability. Structural powder relaxation was carried out in the temperature range of 450 K to 560 K causing considerable changes in the electrical resistivity and magnetic permeability. Upon structural relaxation, the magnetic permeability of the cooled alloy was about 80% higher than the magnetic permeability of the fresh powder. The crystallisation of the amorphous portion of the powder and crystalline grain increase occurred in the 630 K to 900 K temperature interval. Upon crystallisation of the amorphous phase and crystalline grain increase, the powder had about 50% lower magnetic permeability than the fresh powder and 3.6 times lower permeability than the powder where only structural relaxation took place.

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Influence of Gd Addition on the Structure and Capability of Ni-Mn-In Metamagnetic Shape Memory Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.950 ◽

2012 ◽

Vol 535-537 ◽

pp. 950-953

Author(s):

Li Na Bai ◽

Gui Xing Zheng ◽

Zhi Jian Duan ◽

Jian Jun Zhang

Keyword(s):

Differential Scanning Calorimetry ◽

Magnetic Properties ◽

Magnetic Property ◽

Transition Temperature ◽

Martensitic Transformation ◽

Room Temperature ◽

Vibrating Sample Magnetometry ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray

The influences of Gd concentration on martensitic transformation and magnetic properties of NiMnIn alloys were investigated by differential scanning calorimetry (DSC) , vibrating sample magnetometry (VSM), X-ray diffraction (XRD) and etc. It is Observed through the experiment: the addition of Gd enhances martensite transition temperature;X-ray diffraction analysis of experimental alloys is revealed that to the mixture is martensite and austenite at room temperature; content of Gd is not proportional to the improvement of magnetic property.

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