Grain boundary cosegregation and diffusion in Cu(Fe,S) solid solution

1983 ◽  
Vol 31 (7) ◽  
pp. 1047-1052 ◽  
Author(s):  
A. Pineau ◽  
B. Aufray ◽  
F. Cabane-Brouty ◽  
J. Cabane
Keyword(s):  
Solid Solution ◽  
Grain Boundary ◽  
And Diffusion

Grain boundary segregation and diffusion in Ag-S solid solution

1979 ◽  
Vol 27 (12) ◽  
pp. 1849-1854 ◽  
Author(s):  
B. Aufray ◽  
F. Cabane-Brouty ◽  
J. Cabane
Keyword(s):  
Solid Solution ◽  
Grain Boundary ◽  
Boundary Segregation ◽  
Grain Boundary Segregation ◽  
And Diffusion

scholarly journals Microstructure and Magnetic Properties of NdFeB Sintered Magnets Diffusion-Treated with Cu/Al Mixed Dyco Alloy-Powder

2017 ◽  
Vol 62 (2) ◽  
pp. 1263-1266 ◽  
Author(s):  
M.-W. Lee ◽  
K.-H. Bae ◽  
S.-R. Lee ◽  
H.-J. Kim ◽  
T.-S. Jang
Keyword(s):  
Grain Boundary ◽  
Diffusion Path ◽  
Boundary Phase ◽  
Core Shell ◽  
Phase Layer ◽  
Sintered Magnets ◽  
The Core ◽  
Shell Type ◽  
Property Changes ◽  
And Diffusion

AbstractWe investigated the microstructural and magnetic property changes of DyCo, Cu + DyCo, and Al + DyCo diffusion-treated NdFeB sintered magnets. The coercivity of all diffusion treated magnet was increased at 880ºC of 1stpost annealing(PA), by 6.1 kOe in Cu and 7.0 kOe in Al mixed DyCo coated magnets, whereas this increment was found to be relatively low (3.9 kOe) in the magnet coated with DyCo only. The diffusivity and diffusion depth of Dy were increased in those magnets which were treated with Cu or Al mixed DyCo, mainly due to comparatively easy diffusion path provided by Cu and Al because of their solubility with Ndrich grain boundary phase. The formation of Cu/Al-rich grain boundary phase might have enhanced the diffusivity of Dy-atoms. Moreover, relatively a large number of Dy atoms reached into the magnet and mostly segregated at the interface of Nd2Fe14B and grain boundary phases covering Nd2Fe14B grains so that the core-shell type structures were developed. The formation of highly anisotropic (Nd, Dy)2Fe14B phase layer, which acted as the shell in the core-shell type structure so as to prevent the reverse domain movement, was the cause of enhancing the coercivity of diffusion treated NdFeB magnets. Segregation of cobalt in Nd-rich TJP followed by the formation of Co-rich phase was beneficial for the coercivity enhancement, resulting in the stabilization of the metastable c-Nd2O3phase.

Investigating behaviours of hydrogen in a tungsten grain boundary by first principles: from dissolution and diffusion to a trapping mechanism

2010 ◽  
Vol 50 (2) ◽  
pp. 025016 ◽  
Author(s):  
Hong-Bo Zhou ◽  
Yue-Lin Liu ◽  
Shuo Jin ◽  
Ying Zhang ◽  
G.-N. Luo ◽  
...  
Keyword(s):  
Grain Boundary ◽  
First Principles ◽  
Trapping Mechanism ◽  
And Diffusion

Structural and phase equilibria studies in the system Pt-Fe-Cu and the occurrence of tulameenite (Pt2FeCu)

1985 ◽  
Vol 49 (353) ◽  
pp. 547-554 ◽  
Author(s):  
M. Shahmiri ◽  
S. Murphy ◽  
D. J. Vaughan
Keyword(s):  
Crystal Structure ◽  
Solid Solution ◽  
Critical Temperature ◽  
Grain Boundary ◽  
Phase Region ◽  
X Ray Diffraction ◽  
Two Phase ◽  
Slow Cooling ◽  
X Ray ◽  
Diffraction Patterns

AbstractThe crystal structure and compositional limits of the ternary compound Pt2FeCu (tulameenite), formed either by quenching from above the critical temperature of 1178°C or by slow cooling, have been investigated using X-ray diffraction, transmission electron microscopy, differential thermal analysis and electron probe microanalysis.The crystal structure of Pt2FeCu, established using electron density maps constructed from the measured and calculated intensities of X-ray diffraction patterns of powdered specimens, has the (000) and (½½0) lattice sites occupied by Pt atoms and the (½0½) and (0½½) sites occupied by either Cu or Fe atoms in a random manner. The resulting face-centred tetragonal structure undergoes a disordering transformation at the critical temperature to a postulated non-quenchable face-centred cubic structure. Stresses on quenching, arising from the ordering reaction, are relieved by twinning along {101} planes or by recrystallization along with deformation twinning; always involving grain boundary fracturing.Phase relations in the system Pt-Fe-Cu have been investigated through the construction of isothermal sections at 1000 and 600°C. At 1000°C there is an extensive single phase region of solid solution around Pt2FeCu and extending to the binary composition PtFe. At 600°C the composition Pt2FeCu lies just outside this now reduced area of solid solution in a two-phase field. Comparison of the experimental results with data for tulameenite suggests that some observed compositions may be metastably preserved. The occurrence of fine veinlets of silicate or other gangue minerals in tulameenite is suggested to result from grain boundary fracturing on cooling below the critical temperature of 1178°C and to be evidence of a magmatic origin.

Grain boundary random walks and diffusion in polycrystals

1993 ◽  
Vol 193 (2) ◽  
pp. 259-303 ◽  
Author(s):  
I.A. Lubashevskii ◽  
V.L. Alatortsev ◽  
A.G. Keijan
Keyword(s):  
Grain Boundary ◽  
Random Walks ◽  
And Diffusion

Simultaneous measurement of vaporisation rate and diffusion coefficient in the Ni-V solid solution

1980 ◽  
Vol 30 (4) ◽  
pp. 465-468 ◽  
Author(s):  
V. I. Patoka ◽  
V. I. Silantjev ◽  
V. N. Kolesnik ◽  
J. Vřešťál ◽  
B. Million
Keyword(s):  
Solid Solution ◽  
Diffusion Coefficient ◽  
Simultaneous Measurement ◽  
And Diffusion

On the Adhesion of LPCVD WSi2 to Doped and Undoped Polysilicon

1988 ◽  
Vol 119 ◽  
Author(s):  
K. Shenai ◽  
P. A. Piacente ◽  
N. Lewis ◽  
M. D. McConnell ◽  
G. A. Smith ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Chemical Vapor ◽  
Atomic Ratio ◽  
Silicide Film ◽  
Grain Structures ◽  
Integrated Devices ◽  
Chemical Vapor Deposited ◽  
Electrical Conductivities ◽  
Pressure Chemical ◽  
And Diffusion

AbstractWe report on the adhesion characteristics of Low Pressure Chemical Vapor Deposited (LPCVD) WSi2 to doped and undoped polysilicon when used for fabricating silicon discreie and integrated devices. About 3000Å of silicon rich (Si:W atomic ratio of 2.6) LPCVD WSi2 was deposited on 6 kÅ of polysilicon and annealed in nitriding and oxidizing ambients at various temperatures from 1000°C to 1100°C to lower the sheet resistance. Detailed material analyses of as-deposited and annealed polycides were performed using Auger, SIMS, RBS, TEM, and SEM and electrical conductivities of the films were measured using the four point probe. In some samples, the oxide grown on the silicide film was wet etched prior to implanting and diffusing As corresponding to the source/drain diffusions in power FET's. It was observed that polysilicon doping, WSi2 deposition and annealing, oxide or nitride etching, implantation and diffusion of As - all had significant impact on the grain structures of silicide and polysilicon, adhesion of the silicide film to polysilicon, and the electrical conductivity of the silicide. In samples where the oxide grown on the silicide was wet etched, enhanced grain boundary related oxidation of the silicide and polysilicon and seepage of the wet etchant through sequential etching of grain boundary oxide resulted in poor adhesion of WSi2 grains to polysilicon and eventual silicide peeloff. This problem was severe in samples which were not implanted with As but subjected to 900°C, 60 min. source drive.

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