The formation of nanometre crystalline intermetallic compounds in the Ti-face-centred cubic metal (Ni, Cu and Al) binary system by mechanical alloying

Ball milling has been used as a solid-state mechanical alloying technique in two binary systems of plastic crystals: neopentylglycol/pentaglycerin (NPG/PG), showing a partial solubility in the ordered phase, and 2-amino-2-methyl-1,3-propanediol/tris(hydroxymethyl) (AMP/TRIS) whose immiscibility in this ordered solid phase is almost total. For the AMP/TRIS system the stable state at room temperature was reached by milling. Contrarily, for NPG/PG, DSC measurements reveal that an annealing period is required after milling. These results have been compared with those of the pentaglycerin/pentaerythritol (PG/PE) binary system, previously studied, whose miscibility is total at room temperature.

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First-principles studies on phase stability, anisotropic elastic and electronic properties of Al-La binary system intermetallic compounds

Materials Today Communications ◽

10.1016/j.mtcomm.2020.101101 ◽

2020 ◽

Vol 24 ◽

pp. 101101

Author(s):

Fenger Sun ◽

Guowei Zhang ◽

Xiaoyan Ren ◽

Mingjie Wang ◽

Hong Xu ◽

...

Keyword(s):

Binary System ◽

Electronic Properties ◽

Intermetallic Compounds ◽

Phase Stability ◽

First Principles ◽

Anisotropic Elastic

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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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