Pressure-Induced Phase Transition and Mechanical Properties of Mg2Sr Intermetallics
نویسندگان
چکیده
A pressure-induced phase transition of Mg₂Sr intermetallics from the low-pressure C14-type phase to an orthorhombic phase (space group Cmcm, Z = 4) at a high pressure of 21.0 GPa was firstly predicted using first-principles calculations combined with unbiased swarm structure searching techniques. The phase transition was identified as a first-order nature with a volume drop of 4.7%, driven by the softening of elastic behavior at high pressure. Further phonon calculations indicate that the newly predicted orthorhombic phase is dynamically stable at high pressure and ambient pressure. The mechanical properties including the elastic anisotropy of this orthorhombic phase were thus fully studied at ambient pressure. The elastic anisotropy behavior of this orthorhombic phase was investigated by the distributions of elastic moduli. The evidence of the bonding nature of Mg-Sr was also manifested by density of states (DOS) and electronic localization function (ELF) calculations.
منابع مشابه
Effect of Ni on Amorphization of Ti-Cu-Ni Ternary alloys Prepared by Mechanical alloying
Amorphous alloys has been taken into consideration because of their unique properties and are nominated as the future engineering materials. In this research, the effect of Ni and milling time on amorphization process and thermal stability of Ti50Cu50-xNix(x=10, 15, 25 at%) alloy system were investigated. The evolution of amorphization during milling, thermal stability and subsequent heat treat...
متن کاملHIGH PRESSURE BEHAVIOR OF KCl: STRUCTURAL AND ELECTRONIC PROPERTIES
The high pressure behavior of the structural and electronic properties of KC1 is studied with use of the density functional pseudopotential method within local-density approximation. Atzero pressure, the rocksalt phase is found to be lower in energy than CsCl structure. However, we predict a phase transition into CsCI structure at a pressure of about 1.5 GPa. The calculated ground state pro...
متن کاملPhase transition induced strain in ZnO under high pressure
Under high pressure, the phase transition mechanism and mechanical property of material are supposed to be largely associated with the transformation induced elastic strain. However, the experimental evidences for such strain are scanty. The elastic and plastic properties of ZnO, a leading material for applications in chemical sensor, catalyst, and optical thin coatings, were determined using i...
متن کاملA Study on the Mechanical Properties of Dual Phase Steels Prepared by the Direct and Step Quenching Procedure
Two different dual phase steels were prepared from low carbon manganese steel after the elimination of the banding using the direct quenching (DQ) and the step quenching (SQ) procedures. Different heat treatments resulted in different martensite morphologies, microstructures and mechanical properties. The heat treatments were designed in such a way to obtain a 0.25 volume fraction of martensite...
متن کاملEffect of N2 partial pressure on the structural and mechanical properties of TaN films
TaN films with different N2 partial pressure were deposited on 304 stainless steel using the magnetron sputtering method. The effect of gas pressure on the mechanical property, morphology and phase structure of the films is investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), microhardness testing, friction coefficient measurements, and wear mechanism study. The XRD results c...
متن کامل