Effect of alloying elements on lattice misfit and elasticities of Ni-based single crystal superalloys by first-principle calculations

AbstractIdeal sillenite type Bi12FeO20 (BFO) micron sized single crystals have been successfully grown via inexpensive hydrothermal method. The refined single crystal X-ray diffraction data reveals cubic Bi12FeO20 structure with single crystal parameters. Occurrence of rare Fe4+ state is identified via X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The lattice parameter (a) and corresponding molar volume (Vm) of Bi12FeO20 have been measured in the temperature range of 30–700 °C by the X-ray diffraction method. The thermal expansion coefficient (α) 3.93 × 10–5 K−1 was calculated from the measured values of the parameters. Electronic structure and density of states are investigated by first principle calculations. Photoelectrochemical measurements on single crystals with bandgap of 2 eV reveal significant photo response. The photoactivity of as grown crystals were further investigated by degrading organic effluents such as Methylene blue (MB) and Congo red (CR) under natural sunlight. BFO showed photodegradation efficiency about 74.23% and 32.10% for degrading MB and CR respectively. Interesting morphology and microstructure of pointed spearhead like BFO crystals provide a new insight in designing and synthesizing multifunctional single crystals.

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X-ray photoelectron study and first principle calculations of the electronic structure of PbFe1/2Nb1/2O3 single crystal in the ferroelectric and paraelectric phases

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2013.05.229 ◽

2013 ◽

Vol 579 ◽

pp. 401-405 ◽

Cited By ~ 4

Author(s):

A.T. Kozakov ◽

O.E. Polozhentsev ◽

A.V. Soldatov ◽

K.A. Googlev ◽

A.V. Nikolsky ◽

...

Keyword(s):

Electronic Structure ◽

Single Crystal ◽

First Principle ◽

X Ray ◽

First Principle Calculations ◽

Photoelectron Study

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Effect of Alloying Elements on the Electronic Structure of NiAl

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3107 ◽

2005 ◽

Vol 475-479 ◽

pp. 3107-3110 ◽

Cited By ~ 3

Author(s):

Feng Yang ◽

Dong Liang Zhao

Keyword(s):

Electronic Structure ◽

Charge Distribution ◽

Alloying Elements ◽

First Principle ◽

Mulliken Population ◽

Good For ◽

Effect Of Alloying

The change of the electronic structure in NiAl is investigated through DVM-the first principle method when Al in NiAl is substituted by Sc,Ti,V, Cr, Mn, Fe, Co, Ni, Cu, Zn. The results including Mulliken population, the charge distribution and cohesion energies are presented. The calculation of the electronic structure indicates that the substitution atoms take effect on the electronic structure of Ni and Al atoms surrounding the substitution atoms, and the ductility of NiAl. Among the substitution atoms that we studied, Fe, Co and Ni with more d electrons may be good for the ductility of NiAl.

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Effect of Alloying Elements on the Elastic Properties of γ-Ni and γ'-Ni3Al from First-principles Calculations

MRS Proceedings ◽

10.1557/proc-1224-ff05-31 ◽

2009 ◽

Vol 1224 ◽

Cited By ~ 8

Author(s):

Yunjiang Wang ◽

Chongyu Wang

Keyword(s):

Elastic Properties ◽

First Principles ◽

Electronic Structures ◽

Elastic Moduli ◽

Lattice Misfit ◽

Alloying Elements ◽

First Principles Calculations ◽

Strengthening Mechanisms ◽

Two Phases ◽

Effect Of Alloying

AbstractThe effect of alloying elements Ta, Mo, W, Cr, Re, Ru, Co, and Ir on the elastic properties of both γ-Ni and γ′-Ni3Al is studied by first-principles method. Results for lattice properties, elastic moduli and the ductile/brittle behaviors are all presented. Our calculated values agree well with the existing experimental observations. Results show all the additions decrease the lattice misfit between and γ′ phases. Different alloying elements are found to have different effect on the elastic moduli of γ-Ni. Whereas all the alloying elements slightly increase the moduli of γ′-Ni3Al expect Co. Both of the two phases are becoming more brittle with alloying elements, but Co is excepted. The electronic structures of γ′ phase alloyed with different elements are provided as example to elucidate the different strengthening mechanisms.

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Dv-X α First Principle Analysis of the Effect of Alloying Elements on the α” Phase Formation in Ti Alloys

Proceedings of the 13th World Conference on Titanium ◽

10.1002/9781119296126.ch111 ◽

2016 ◽

pp. 669-675

Author(s):

Sengo Kobayashi ◽

Riku Wakamoto ◽

Tatsuaki Sakamoto

Keyword(s):

Phase Formation ◽

Alloying Elements ◽

First Principle ◽

Ti Alloys ◽

Α Phase ◽

Effect Of Alloying

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The role of alloying elements on the structural, mechanical and thermodynamic properties of Al3X binary alloy system (X = Mg, Sc and Zr): first principle calculations

Materials Research Express ◽

10.1088/2053-1591/aa9485 ◽

2017 ◽

Vol 4 (11) ◽

pp. 116502 ◽

Cited By ~ 2

Author(s):

F Bakare ◽

M I Babalola ◽

B E Iyorzor

Keyword(s):

Thermodynamic Properties ◽

Binary Alloy ◽

Alloy System ◽

Alloying Elements ◽

First Principle ◽

First Principle Calculations ◽

Binary Alloy System

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Strengthening Mechanisms in Some Single-Crystal Superalloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.623 ◽

2005 ◽

Vol 475-479 ◽

pp. 623-626 ◽

Cited By ~ 1

Author(s):

Yuichiro Koizumi ◽

Hiroshi Harada

Keyword(s):

High Temperature ◽

Single Crystal ◽

Creep Behavior ◽

Lattice Misfit ◽

Alloying Elements ◽

Strengthening Mechanisms ◽

Interfacial Dislocation ◽

Nickel Base

The creep behavior and microstructure of several nickel-base single-crystal superalloys after high-temperature low-stress creep have been investigated. These alloys were designed with varying content of the alloying elements Mo and Ru. At 1100°C and 137 MPa, the large g/g¢ lattice misfit in negative with the addition of Mo leads to the formation of dense interfacial dislocation networks. These dislocation networks are effective to strengthen the alloys during creep by preventing the penetration of the g dislocations into the g¢ phase.

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Vibrational spectroscopy of orthorhombic Cu 2 ZnSiS 4 single crystal: Low-temperature polarized Raman scattering and first principle calculations

Vibrational Spectroscopy ◽

10.1016/j.vibspec.2017.01.005 ◽

2017 ◽

Vol 89 ◽

pp. 81-84 ◽

Cited By ~ 1

Author(s):

M. Ya. Valakh ◽

V.O. Yukhymchuk ◽

I.S. Babichuk ◽

Ye. O. Havryliuk ◽

O.V. Parasyuk ◽

...

Keyword(s):

Low Temperature ◽

Raman Scattering ◽

Single Crystal ◽

Vibrational Spectroscopy ◽

First Principle ◽

First Principle Calculations ◽

Polarized Raman

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Effects of Re on Microstructure of Ni3Al-Based Single Crystal Superalloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.498 ◽

2014 ◽

Vol 788 ◽

pp. 498-503 ◽

Cited By ~ 1

Author(s):

Jing Yang Chen ◽

Ming Xue ◽

Xin Tang ◽

La Mei Cao

Keyword(s):

Single Crystal ◽

Volume Fraction ◽

Lattice Misfit ◽

Alloying Elements ◽

Microstructural Stability ◽

Segregation Ratios ◽

Kinetics Of ◽

Liquidus Temperatures

The effects of Re on solidus/liquidus temperatures, solidification segregation characteristics of alloying elements, γ′ morphology and volume fraction as well as microstructural stability at 1150 °C have been investigated in two experimental Ni3Al-based single crystal superalloys with and without Re (1.0 wt%) addition. The results indicated that Re addition increased the solidus/liquidus temperatures. The segregation characteristics of Ni3Al-based single crystal superalloys were similar with Ni-based single crystal superalloys, and the solidification segregation ratios of W and Mo increased slightly due to Re addition. Meanwhile, Re addition resulted in more negative lattice misfit, more cuboidal γ′ phase and higher γ′ volume fraction. The kinetics of γ′ coarsening and rafting at 1150 °C was lowered substantially compared with the addition of Re.

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