Preparation of Ti-22Al-25Nb solid solution powders using mechanical alloying and solid solution mechanism analysis

Molecular dynamic simulations have been performed to study the solid solution mechanism of Mg100-xREx (RE=Gd,Dy,Y, x=0.5,1,2,3,4 at.%). The obtained results reveal that the additions of Gd, Dy and Y increase the lattice constants of Mg-RE alloys. Also the axis ratio c/a remains unchanged with increase in temperature, restraining the occurrence of nonbasal slip and twinning. Furthermore, it is confirmed that bulk modulus of Mg alloys can be increased remarkably by adding the Gd, Dy, Y, especially Gd, because the solid solubility of Gd in Mg decrease sharply with temperature in comparison with Dy and Y. Consequently, the addition of the RE can enhance the strength of Mg-based alloys, which is in agreement with the experimental results.

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Neutron Diffraction Studies on the Structure and Conduction Mechanism in Al, Ga—DOPED Li4SiO4

MRS Proceedings ◽

10.1557/proc-210-593 ◽

1990 ◽

Vol 210 ◽

Author(s):

R.I. Smith ◽

A.R. West

Keyword(s):

Solid Solution ◽

Neutron Diffraction ◽

Solid Solutions ◽

Conduction Mechanism ◽

One Dimensional ◽

Linear Defects ◽

Solution Mechanism

AbstractCrystallographic results on the Li4-3x(Al,Ga)xSiO4 solid solutions are reviewed. The six sets of sites available for Li+ ions fall into two groups. The ‘framework’ sites, which also contain the substitutional Al,Ga ions, appear to have little effect on conductivity. The ‘channel’sites contain varying amounts of Li+ ions and are responsible for the dramatic variations in conductivity with x. There is evidence for the presence of one—dimensional defects, comprising columns of ordered Li+ ions, in both the framework and channel sites. The relative numbers of these linear defects has a large bearing on the solid solution mechanism in the framework sites and their occurrence in the channel sites may be responsible for the low conductivity in stoichiometric Li4SiO4.

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Elaboration, Structure and Mössbauer Spectroscopy of Nanostructured Fe100−xSix Powders Elaborated by Mechanical Alloying

SPIN ◽

10.1142/s2010324717500023 ◽

2017 ◽

Vol 07 (02) ◽

pp. 1750002 ◽

Cited By ~ 1

Author(s):

M. Hemmous ◽

A. Guittoum

Keyword(s):

Magnetic Field ◽

Solid Solution ◽

Mechanical Alloying ◽

Hyperfine Magnetic Field ◽

Lattice Parameter ◽

X Ray Diffraction ◽

X Ray ◽

Grain Sizes ◽

The Mean ◽

Xrd Studies

We have studied the effect of the silicon concentration on the structural and hyperfine properties of nanostructured Fe[Formula: see text]Six powders ([Formula: see text], 20, 25 and 30[Formula: see text]at.%) prepared by mechanical alloying. The X-ray diffraction (XRD) studies indicated that after 72[Formula: see text]h of milling, the solid solution bcc-[Formula: see text]-Fe(Si) is formed. The grain sizes, [Formula: see text]D[Formula: see text] (nm), decreases with increasing Si concentration and reaches a minimum value of 11[Formula: see text]nm. We have found that the lattice parameter decreases with increasing Si concentration. The changes in values are attributed to the substitutional dissolution of Si in Fe matrix. From the adjustment of Mössbauer spectra, we have shown that the mean hyperfine magnetic field, [Formula: see text]H[Formula: see text] (T), decreases with increasing Si concentration. The substitutional dependence of [Formula: see text]H[Formula: see text] (T) can be attributed to the effect of p electrons Si influencing electrons d of Fe.

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Formation of Al-Fe Supersaturated Solid Solution by Mechanical Alloying

Materials Science Forum ◽

10.4028/www.scientific.net/msf.88-90.481 ◽

1992 ◽

Vol 88-90 ◽

pp. 481-488 ◽

Cited By ~ 19

Author(s):

V.I. Fadeeva ◽

Alexandr V. Leonov

Keyword(s):

Solid Solution ◽

Mechanical Alloying ◽

Supersaturated Solid Solution

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Synthesis and characterization of nanocrystalline AlFeTiCrZnCu high entropy solid solution by mechanical alloying

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2007.05.104 ◽

2008 ◽

Vol 460 (1-2) ◽

pp. 253-257 ◽

Cited By ~ 173

Author(s):

S. Varalakshmi ◽

M. Kamaraj ◽

B.S. Murty

Keyword(s):

Solid Solution ◽

Mechanical Alloying ◽

Synthesis And Characterization ◽

High Entropy

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The formation of metastable Ti–Al solid solutions by mechanical alloying and ball milling

Journal of Materials Research ◽

10.1557/jmr.1993.2819 ◽

1993 ◽

Vol 8 (11) ◽

pp. 2819-2829 ◽

Cited By ~ 71

Author(s):

M. Oehring ◽

T. Klassen ◽

R. Bormann

Keyword(s):

Solid Solution ◽

Mechanical Alloying ◽

Ball Milling ◽

Intermetallic Compounds ◽

Phase Formation ◽

Milling Process ◽

Study Phase ◽

Phase Selection ◽

Powder Blends ◽

Al Powder

Elemental Ti–Al powder blends were mechanically alloyed in order to study phase formation during the alloying process. In addition, the stability of intermetallic phases upon milling was investigated separately in order to determine the origins of phase selection during the milling process. It was found that by mechanical alloying of powder blends, as well as by ball milling of Ti-aluminides for long milling times, the same metastable phases were formed for corresponding compositions, i.e., the hep solid solution for Al concentrations up to 60 at. % and the fcc solid solution for 75 at. % Al. X-ray diffraction (XRD) analyses indicated that the process of mechanical alloying occurred via the diffusion of Al into Ti. By lowering the milling intensity, a two-phase mixture of the hcp solid solution and the amorphous phase was observed for Ti50Al50 and confirmed by transmission electron microscopy (TEM). The results show that phase selection in the final state during mechanical alloying of Ti–Al powder blends and milling of intermetallic compounds is mainly determined by the energetic destabilization of the competing phases caused by the milling process. The destabilization is most pronounced in the case of intermetallic compounds due to the decrease in long-range order upon milling. For the final milling stage, phase formation can be predicted by considering the relative stabilities of the respective phases calculated by the CALPHAD method using the available thermodynamic data for the Ti–Al system.

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THEORETICAL CALCULATION OF ATOMIC STRAIN ON MECHANICAL ALLOYED METASTABLE INTERMETALLIC

Surface Review and Letters ◽

10.1142/s0218625x09012433 ◽

2009 ◽

Vol 16 (01) ◽

pp. 157-160

Author(s):

L. PANG ◽

J. XU ◽

J. ZHANG

Keyword(s):

Solid Solution ◽

Solid State ◽

Binary System ◽

Mechanical Alloying ◽

Theoretical Calculation ◽

Solid State Reaction ◽

Lattice Strain ◽

Electron Theory ◽

Strain Behavior ◽

Good Coincidence

Mechanical alloying (MA) has been utilized to synthesize many equilibrium and/or nonequilibrium phases. During the MA process, alloys are formed by the solid-state reaction. Solid solution has been obtained by MA, strain occurs due to the dissolution one component in the binary system. An understanding of the strain in mechanical alloyed Ti – Al , Fe – Al , Ni – Al from the electronic level has remained elusive. In this communication, atomic strain behavior of Ti – Al , Fe – Al , Ni – Al systems is analyzed on the basis of the TFDC (abbreviation of the name of Thomas, Fermi, Dirac, and Cheng) electron theory. Lattice strain of Ti , Fe , Ni , and Al are compared with available experimental results. A very good coincidence was found.

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