scholarly journals Effect of Small Additions of Cr, Ti, and Mn on the Microstructure and Hardness of Al–Si–Fe–X Alloys

Metals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 136 ◽  
Author(s):  
Víctor Aranda ◽  
Ignacio Figueroa ◽  
Gonzalo González ◽  
J. García-Hinojosa ◽  
Gabriel Lara-Rodríguez
Keyword(s):  
Vickers Microhardness ◽  
Melting Furnace ◽  
Alloy System ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
Microstructural Refinement ◽  
X Ray ◽  
Arc Melting ◽  
Elemental Chemical Analysis ◽  
Mn Additions

The Al–Si–Fe system has drawn the attention of the scientific community due to its capacity to replace parts in several manufacturing industries, as this alloy system is very sensitive to small additions of transition metals. Therefore, the aim of this work is to study the effect of Cr, Ti, and Mn additions in the Al–20Si–5Fe (wt. %) alloy and to study the modification of the iron intermetallic and the microstructural refinement through the formation of secondary phases. Al–20Si–5Fe–X (X = Cr, Mn and Ti at 1.0, 3.0, and 5.0 wt. %) alloy ingots were prepared by arc melting furnace. The elemental chemical analysis was performed by X-ray fluorescence spectrometry (XRF). The microstructure of all samples was investigated by scanning electron microscopy and X-ray diffraction. Finally, microhardness was measured in order correlate the hardness with the formation of the different compounds. The highest hardness was found for the alloy with the 5 wt. % Cr. The addition of Ti and Mn raised the hardness by ~35 HVN (Vickers microhardness) when compared to that of AlSiFe master alloy. Important changes were also observed in the microstructure. Depending on the Cr, Ti, and Mn additions, the resulting microstructure was dendritic (CrFe), acicular (Ti5Si3), and “bone like” (Mn0.2Fe0.8), respectively.

Effects of Cooling Rate and Sn Addition on the Microstructure of Ti-Nb-Sn Alloys

2011 ◽  
Vol 172-174 ◽  
pp. 190-195 ◽  
Author(s):  
Giorgia T. Aleixo ◽  
Eder S.N. Lopes ◽  
Rodrigo Contieri ◽  
Alessandra Cremasco ◽  
Conrado Ramos Moreira Afonso ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cooling Rate ◽  
Melting Furnace ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Β Phase ◽  
Arc Melting ◽  
Ti Alloys ◽  
Ω Phase

Ti-based alloys present unique properties and hence, are employed in several industrial segments. Among Ti alloys, β type alloys form one of the most versatile classes of materials in relation to processing, microstructure and mechanical properties. It is well known that heat treatment of Ti alloys plays an important role in determining their microstructure and mechanical behavior. The aim of this work is to analyze microstructure and phases formed during cooling of β Ti-Nb-Sn alloy through different cooling rates. Initially, samples of Ti-Nb-Sn system were prepared through arc melting furnace. After, they were subjected to continuous cooling experiments to evaluate conditions for obtaining metastable phases. Microstructure analysis, differential scanning calorimetry and X-ray diffraction were performed in order to evaluate phase transformations. Depending on the cooling rate and composition, α” martensite, ω phase and β phase were obtained. Elastic modulus has been found to decrease as the amount of Sn was increased.

Synthesis, Crystal Chemistry and Magnetism of the Metal-rich Borides MxRh7–xB3 (M = Cr, Mn, Ni; x = 0.39–1) with Th7Fe3-type Structure

2011 ◽  
Vol 66 (12) ◽  
pp. 1241-1247
Author(s):  
Patrick R.N. Misse ◽  
Richard Dronskowski ◽  
Boniface P. T. Fokwa
Keyword(s):  
Melting Furnace ◽  
Structure Type ◽  
Argon Atmosphere ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Arc Melting ◽  
Pauli Paramagnetism ◽  
Powder Samples ◽  
Boride Phases

Powder samples and single crystals of the boride phases MxRh7−xB3 (M = Cr,Mn, Ni; x ≤ 1) have been synthesized from the elements using an arc-melting furnace under purified argon atmosphere in a water-cooled copper crucible. The new phases were characterized from single-crystal and powder X-ray diffraction, as well as semi-quantitative EDX measurements. The obtained phases crystallize in the hexagonal Th7Fe3 structure type (space group P63mc, no. 186, Z = 2). In all cases (M = Cr, Mn, Ni), M is found to preferentially mix with rhodium at only one (6c) of the three available rhodium positions. Pauli paramagnetism was observed in CrxRh7−xB3 (x < 1), whereas both Pauli and temperature-dependent paramagnetisms were found in NiRh6B3.

Condensed [Ru4Sn6] Units in the Stannides LnRu4Sn6 (Ln = La, Pr, Nd, Sm, Gd) - Synthesis, Structure, and Chemical Bonding

1999 ◽  
Vol 54 (7) ◽  
pp. 863-869 ◽  
Author(s):  
Markus F. Zumdick ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Single Crystals ◽  
Chemical Bonding ◽  
Melting Furnace ◽  
Structural Motif ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
First Time ◽  
Gadolinium Compound

The stannides LnRu4Sn6 (Ln = La, Pr, Nd, Sm, Gd) were prepared by reaction of the elements in an arc-melting furnace and subsequent annealing at 1120 K. The praseodymium, the neodymium, and the samarium stannide were obtained for the first time. The LnRu4Sn6 stannides were investigated by X-ray diffraction both on powders and single crystals. They adopt the YRu4Sn6 type structure which was refined from single crystal X-ray data for the samarium and the gadolinium compound: I4̄2m, a = 686.1 (1), c = 977.7(2) pm, wR2 = 0.0649, 483 F2 values for SmRu4Sn6, and a = 685.2(1), c = 977.6(3) pm, wR2 = 0.0629, 554 F2 values for GdRu4Sn6 with 19 variables for each refinement. The striking structural motif of these stannides are distorted RuSn6 octahedra with Ru-Sn distances ranging from 257 to 278 pm. Four of such octahedra are condensed via common edges and faces forming [Ru4Sn6] units which are packed in a tetragonal body-centered arrangement. The rare-earth atoms fill the voids between the [Ru4Sn6] units. Based on an extended Hückel calculation, strong bonding interactions were found for the Ru-Sn and the various Sn-Sn contacts.

The Stannide Zr5CuSn3

1997 ◽  
Vol 52 (1) ◽  
pp. 141-144 ◽  
Author(s):  
Rainer Pöttgen
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Melting Furnace ◽  
Type Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting

Zr5CuSn3 was prepared from the elements in an arc-melting furnace and investigated by X-ray diffraction of powders as well as of single crystals. The crystal structure was refined from four-circle diffractometer data: P63/mcm, a = 860.04(7) pm, c = 586.80(5) pm, V = 0.3759(1) nm3, Z = 2, wR2 = 0.0402 for 371 F2 values and 15 variables. A refinement of the occupancy parameters re­vealed that the copper position is occupied to only 95.3(8)% in the crystal used for the X-ray investigation. Zr5CuSn3 crystallizes in the Hf5CuSn3 type structure, a filled variant of the Mn5Si3 type. The main features of the Zr5CuSn3 structure are condensed Zr6 octahedra that are centered by copper atoms

Obtaining of Nanoapatite in Ti-7.5Mo Surface after Nanotube Growth

2012 ◽  
Vol 727-728 ◽  
pp. 1199-1204 ◽  
Author(s):  
A.L.A. Escada ◽  
João Paulo Barros Machado ◽  
Roberto Zenhei Nakazato ◽  
Ana Paula Rosifini Alves Claro
Keyword(s):  
Thin Film ◽  
Biomedical Applications ◽  
Melting Furnace ◽  
Material Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
Cold Worked ◽  
Nanotube Growth ◽  
Scanning Electron

Titanium and their alloys have been used for biomedical applications due their excellent mechanical properties, corrosion resistance and biocompatibility. However, they are considered bioinerts materials because when they are inserted into the human body they are cannot form a chemical bond with bone. In several studies, the authors have attempted to modify their characteristic with treatments that changes the material surface. The purpose of this work was to evaluate obtaining of nanoapatite after growing of the nanotubes in surface of Ti-7.5Mo alloy. Alloy was obtained from c.p. titanium and molibdenium by using an arc-melting furnace. Ingots were submitted to heat treatment and they were cold worked by swaging. Nanotubes were processed using anodic oxidation of alloy in electrolyte solution. Surfaces were investigated using scanning electron microscope (SEM), FEG-SEM and thin-film x-ray diffraction. The results indicate that nanoapatite coating could form on surface of Ti-7.5Mo experimental alloy after nanotubes growth.

Investigation of the Solidified Structure of Cu-Hf-Ti Alloys

2010 ◽  
Vol 649 ◽  
pp. 81-86
Author(s):  
Viktória Rontó ◽  
E. Nagy ◽  
Mária Svéda ◽  
Ferenc Tranta ◽  
Norbert Hegman
Keyword(s):  
Centrifugal Casting ◽  
Dendritic Structure ◽  
Alloy System ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
Ti Alloys ◽  
Cooling Conditions ◽  
Master Alloys ◽  
Wedge Shape

Master alloys with different compositions of the Cu-Hf-Ti alloy system were prepared by arc-melting. The pieces were then cast into a wedge- and rod – shaped Cu mould by centrifugal casting. The different mould shapes generated various cooling conditions and produced various microstructures in the samples. Moreover due to the wedge shape, the change of the microstructure can be observed within the samples. The wedge samples became amorphous in 1-1.5 mm thickness, and dendritic structure formed in the thicker parts. The change in the microstructure in the rod samples along the radius can be studied as well. The solidified phases were also investigated by X-ray diffraction and SEM-EDAX.

New Indides EuAuIn2, EuPdIn4, GdRhIn2, YbRhIn4, and YbPdIn4

2000 ◽  
Vol 55 (9) ◽  
pp. 834-840 ◽  
Author(s):  
Rolf-Dieter Hoffmann ◽  
Rainer Pöttgen ◽  
Vasyl’ I. Zaremba ◽  
Yaroslav M. Kalychak
Keyword(s):  
High Frequency ◽  
Three Dimensional ◽  
Melting Furnace ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Type Space ◽  
Arc Melting ◽  
Indium Compounds ◽  
Host Lattices

New intermetallic indium compounds EuAuIn2, EuPdIn4, GdRhIn2, YbRhln4, and YbPdIn4 were obtained by reaction of the elements. GdRhIn2 was synthesized in an arc-melting furnace, while EuAuIn2, EuPdln4, YbRhIn4, and YbPdIn4 were prepared in sealed tantalum tubes in a high-frequency furnace. The five compounds were investigated by X-ray diffraction both on powders and single crystals. EuAuIn2 and GdRhIn2 adopt the MgCuAl2 type structure with space group Cmcm. Single crystal X-ray data yielded a = 468.1(2), b = 1105.5(4), c = 753.5(4) pm, wR2 = 0.096, 343 F2 values for EuAuIn2 and a = 435.0(1), b = 1013.3(3), c = 783.6(2) pm, wR2 = 0.042, 608 F2 values for GdRhIn2 with 16 variables for each refinement. The two structures may be described as gold or rhodium filled versions of the host lattices Euln2 and GdIn2 . The three-dimensional indium networks of EuAuIn2 and GdRhIn2 resemble the lonsdaleite structure. Both structures are built up from three-dimensional [Auln2] and [Rhln2] poly anions in which the europium and gadolinium atoms occupy distorted hexagonal tubes. The modulations of the In-In distances within the indium networks are compared with other MgCuAl2 type indides. EuPdIn4 and YbPdIn4 crystallize with the YNiAl4 type, space group Cmcm: a = 454.8(2), b = 1703.2(8), c = 738.0(3) pm, wR2 = 0.044, 501 F2 values for EuPdIn4 and a = 445.8(2), b = 1666.0(4), c = 747.3(2) pm, wR2 = 0.050, 711 F2 values for YbPdIn4 with 24 variables for each refinement. In contrast, YbRhln4 adopts the LaCoAl4 type, space group Pmma: a = 863.7(2), b = 422.5(1), c = 743.1(1) pm, wR2 = 0.051, 467 F2 values and 24 variables. EuPdIn4, YbPdlIn4, and YbRhIn4 too consist of three-dimensional [Pdln4] and [Rhln4] polyanions in which the europium and ytterbium atoms are located in distorted hexagonal and pentagonal channels. Common structural motifs of these indides are distorted bcc-like indium cubes which are compared with the structures of Y2CoIn8, YCoIn5, EuRh2ln8, and elemental indium. Chemical bonding in these indides is briefly discussed

New Coordination Compounds of Fe(III) with Organic Ligands

2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Mihaela Flondor ◽  
Ioan Rosca ◽  
Doina Sibiescu ◽  
Mihaela-Aurelia Vizitiu ◽  
Daniel-Mircea Sutiman ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Complex Compounds ◽  
Organic Ligands ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Chemical Analysis ◽  
Structural Formulae ◽  
Paramagnetic Properties

In this paper the synthesis and the study of some complex compounds of Fe(III) with ligands derived from: 2-(4-chloro-phenylsulfanyl)-1-(2-hydroxy-3,5-diiodo-phenyl)-ethanone (HL1), 1-(3,5-dibromo-2-hydroxy-phenyl)-2-phenylsulfanyl-ethanone(HL2), and 2-(4-chloro-phenylsulfanyl)-1-(3,5-dibromo-2-hydroxy-phenyl)-ethanone (HL3) is presented. The characterization of these complexes is based on method as: the elemental chemical analysis, IR and ESR spectroscopy, M�ssbauer, the thermogravimetric analysis and X-ray diffraction. Study of the IR and chemical analysis has evidenced that the precipitates form are a complexes and the combination ratio of M:L is 1:2. The central atoms of Fe(III) presented paramagnetic properties and a octaedric hybridization. Starting from this precipitation reactions, a method for the gravimetric determination of Fe(III) with this organic ligands has been possible. Based on the experimental data on literature indications, the structural formulae of the complex compounds are assigned.

scholarly journals Irregular Electrodeposition of Cu-Sn Alloy Coatings in [EMIM]Cl Outside the Glove Box with Large Layer Thickness

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 310
Author(s):  
Lars Lehmann ◽  
Dominik Höhlich ◽  
Thomas Mehner ◽  
Thomas Lampke
Keyword(s):  
Layer Thickness ◽  
Alloy System ◽  
Liquid Solution ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
X Ray ◽  
Argon Stream ◽  
Ionic Liquid Solution ◽  
The Relationship ◽  
Layer Composition

Thick Cu−Sn alloy layers were produced in an [EMIM]Cl ionic-liquid solution from CuCl2 and SnCl2 in different ratios. All work, including the electrodeposition, took place outside the glovebox with a continuous argon stream over the electrolyte at 95 °C. The layer composition and layer thickness can be adjusted by the variation of the metal-salts content in the electrolyte. A layer with a thickness of up to 15 µm and a copper content of up to ωCu = 0.86 was obtained. The phase composition was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray fluorescence (XRF). Furthermore, it was found that the relationship between the alloy composition and the concentration of the ions in the electrolyte is described as an irregular alloy system as according to Brenner. Brenner described such systems only for aqueous electrolytes containing complexing agents such as cyanide. In this work, it was confirmed that irregular alloy depositions also occur in [EMIM]Cl.

scholarly journals Study of Structural, Magnetic, and Mossbauer Properties of Dy2Fe16Ga1−xNbx (0.0 ≤ x ≤ 1.0) Prepared via Arc Melting Process

2021 ◽  
Vol 7 (3) ◽  
pp. 42
Author(s):  
Jiba N. Dahal ◽  
Kalangala Sikkanther Syed Ali ◽  
Sanjay R. Mishra
Keyword(s):  
Isomer Shift ◽  
Cell Volume ◽  
Intermetallic Compounds ◽  
Unit Cell Volume ◽  
Rietveld Analysis ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
Nb Content

Intermetallic compounds of Dy2Fe16Ga1−xNbx (x = 0.0 to 1.00) were synthesized by arc melting. Samples were investigated for structural, magnetic, and hyperfine properties using X-ray diffraction, vibration sample magnetometer, and Mossbauer spectrometer, respectively. The Rietveld analysis of room temperature X-ray diffraction data shows that all the samples were crystallized in Th2Fe17 structure. The unit cell volume of alloys increased linearly with an increase in Nb content. The maximum Curie temperature Tc ~523 K for x = 0.6 sample is higher than Tc = 153 K of Dy2Fe17. The saturation magnetization decreased linearly with increasing Nb content from 61.57 emu/g for x = 0.0 to 42.46 emu/g for x = 1.0. The Mössbauer spectra and Rietveld analysis showed a small amount of DyFe3 and NbFe2 secondary phases at x = 1.0. The hyperfine field of Dy2Fe16Ga1−xNbx decreased while the isomer shift values increased with the Nb content. The observed increase in isomer shift may have resulted from the decrease in s electron density due to the unit cell volume expansion. The substantial increase in Tc of thus prepared intermetallic compounds is expected to have implications in magnets used for high-temperature applications.

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