Self‐diffusion coefficients of oxygen ion in single crystals of MgO · n Al2O3 spinels

1974 ◽  
Vol 61 (2) ◽  
pp. 625-629 ◽  
Author(s):  
Ken Ando ◽  
Y. Oishi
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Self Diffusion ◽  
Oxygen Ion

Self-diffusion in gold single crystals at low temperatures

1968 ◽  
Vol 46 (23) ◽  
pp. 2589-2594 ◽  
Author(s):  
J. L. Whitton ◽  
G. V. Kidson
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Low Temperatures ◽  
Bulk Diffusion ◽  
Lattice Diffusion ◽  
Fast Diffusion ◽  
Initial Portion ◽  
Self Diffusion ◽  
Normal Lattice ◽  
Structure Sensitive

Self-diffusion in gold single crystals has been studied at temperatures between 335 to 390 °C for times between 15 and 30 min. The concentration profiles, obtained by use of a sensitive sectioning technique, consist of a region that appears to be characteristic of bulk diffusion, followed by a deeply penetrating 'tail' that is structure sensitive. Diffusion coefficients extracted from the initial portion of the curves are somewhat larger than those predicted from an extrapolation of high temperature measurements. The results are interpreted in terms of a combination of normal lattice diffusion and fast diffusion along dislocations.

Dislocation-enhanced diffusion in silver single crystals

1970 ◽  
Vol 48 (13) ◽  
pp. 1548-1552 ◽  
Author(s):  
C. T. Lai ◽  
H. M. Morrison
Keyword(s):  
Crystal Lattice ◽  
Single Crystals ◽  
Diffusion Coefficients ◽  
Enhanced Diffusion ◽  
Temperature Range ◽  
Self Diffusion

An electrolytic sectioning technique has been used to measure self-diffusion coefficients in silver single crystals in the temperature range 300–800 °C. The results are analyzed in terms of diffusion through the crystal lattice, enhanced by diffusion along dislocations.

Self-Diffusion in Tin Crystals

1950 ◽  
Vol 3 (1) ◽  
pp. 91 ◽  
Author(s):  
PJ Fensham
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Vacancy Mechanism ◽  
Self Diffusion ◽  
Active Isotope

The rate of self-diffusion in single crystals of white tin of various orientations has been measured using the radio-active isotope Sn113. The ratio of the diffusion coefficients parallel and perpendicular to the tetragonal (c) axis is approximately 2 at 180 �C. and approximately 3 at 223 �C. The diffusion coefficients in both directions at various temperatures are given by the Arrhenius expressions Dc= 1.2 x 10-5e-10,1500/RT cm.2sec.-1 and Da=3.7 X 10-8e-5,900/RT cm.2sec.-l. The anisotropy is discussed in terms of the vacancy mechanism of diffusion.

First Study of Iron Self-Diffusion in Fe2O3 Single Crystals by SIMS

2005 ◽  
Vol 237-240 ◽  
pp. 277-281 ◽  
Author(s):  
Antônio Claret Soares Sabioni ◽  
Antônio Márcio J.M. Daniel ◽  
W.A.A. Macedo ◽  
M.D. Martins ◽  
Anne Marie Huntz ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Stable Isotope ◽  
Single Crystals ◽  
Diffusion Coefficients ◽  
Secondary Ion Mass Spectrometry ◽  
Depth Profiling ◽  
Reliable Data ◽  
Oxygen Atmosphere ◽  
Self Diffusion ◽  
Secondary Ion

Iron bulk self-diffusion coefficients were measured in Fe2O3 single crystals using an original methodology based on the utilization of 57Fe stable isotope as iron tracer and depth profiling by secondary ion mass spectrometry (SIMS). The iron self-diffusion coefficients measured along c-axis direction, between 900 and 1100o C, in oxygen atmosphere, can be described by the following Arrhenius relationship: D(cm2/s)= 5.2x106 exp [-510 (kJ/mol)/RT], and are similar to reliable data available in the literature, obtained by means of radioactive techniques.

Interphase Boundary Diffusion in Eutectic Alloys

1985 ◽  
Vol 57 ◽  
Author(s):  
G. A. Chadwick
Keyword(s):  
Diffusion Coefficient ◽  
Single Crystal ◽  
Single Crystals ◽  
Interphase Boundary ◽  
Diffusion Coefficients ◽  
Noble Metals ◽  
Boundary Diffusion ◽  
Eutectic Alloys ◽  
Self Diffusion ◽  
Interphase Boundaries

AbstractTurnbull and co-workers have shown that the noble metals Cu, Ag, and Au diffuse into single crystals of Pb and Sn by an interstitialcy mechanism with measured diffusion coefficients of ∼10−6cm2s−1. These experiments have been extended to study the diffusion rates of the noble metals along the interphase boundaries of single crystal of Pb-Sn eutectic alloys and to measure the diffusion coefficient of silver along the interphase boundaries of Ag-Cu eutectic single crystals.The measured interphase boundary diffusion coefficients of the noble metals in the Pb-Sn single crystals are extremely high, being 2.6 × 10−3cm2s−1for Cu and ∼10−4cm2s−1for Ag and Au at room temperature. These results again imply an interstitialcy mechanism of diffusion at the interphase boundaries. In contrast, the diffusion coefficient of Ag110in a Ag-Cu eutectic single crystal worked out to be ∼8×10−9cm2s−1at 500°C, two orders of magnitude lower than the value obtained by Turnbull and Hoffman for self-diffusion along low-angle (8∼10°) boundaries in silver.

Bulk Diffusion of Homovalent Atomic Probes of Vanadium and Niobium in Single Crystals of Tungsten

2012 ◽  
Vol 330 ◽  
pp. 1-10 ◽  
Author(s):  
S.M. Klotsman ◽  
G.N. Tatarinova ◽  
Alexander N. Timofeev
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Secondary Ion Mass Spectrometry ◽  
Volume Diffusion ◽  
Bulk Diffusion ◽  
Self Diffusion ◽  
Arrhenius Dependence ◽  
The Difference ◽  
Defect Interactions ◽  
Secondary Ion

The Volume Diffusion of Homovalent Atomic Probes (APs) from the VB Group of the Periodic Ta-Ble of Elements (PTE) – V and Nb in W Single Crystals Has Been Studied by Using the Method of Secondary Ion Mass Spectrometry (SIMS). the Parameters of the Arrhenius Dependence of the Coefficients DV of Vanadium Volume Diffusion in W Have Been Measured: (D0)V = (1.3  0.4) X 10-4 M2s-1 and QV = (564 ± 6) Kj/mol. the Parameters (D0,Q)Nb of the Bulk Diffusion of Nb Aps in W Have Been Estimated with the Help of Several Measured Coefficients Dnb and the Empirical Correlation [1,2]: (D = DWW)(Tm)W: the Diffusion Coefficients of Substitutional Non-Magnetic 5d-Aps Coincide with the Self-Diffusion Coefficients in W at its Melting Point (Tm)W. the Enthalpies Qnb,Ta of the Bulk Diffusion of Non-Magnetic (nm) Homovalent Aps from the VB Group of PTE – Nb and Ta [3] Also Coincide with the Relaxation Volumes vacVBAPs of Complexes “vacancies-VB Aps” in the W Lattice. Electron Contributions (EDN)vacVBAPs to the Energies Evacvbaps of Interaction of Point Defects in Complexes “vacancies- VB Nm- Aps” Are Lower than in Complexes “vacancies-IVB Nm- Aps” [4]. the Dependence of {EDN(n)}vacVBAPs the Electron Contributions (EDN)vacVBAPs on the Difference of N Numbers of Periods of PTE the Deviation of Contributions (EDN)vacVAPs for Vanadium Aps to En-Ergies Evacvaps of their Interaction in Complexes “vacancy-VAP” Has Been Determined. this Devi-Ation Is Conditioned by the Contribution of the Exchange Energy (Eexch)VAP of Vanadium to the En-Ergy Evacvaps of the Point-Defect Interactions in the Complex “vacancy-VAP”.

Bulk Diffusion of Homovalent Non-Magnetic Atomic Probes of Titanium and Zirconium in Tungsten Single Crystals

2011 ◽  
Vol 319-320 ◽  
pp. 1-11 ◽  
Author(s):  
S.M. Klotsman ◽  
G.N. Tatarinova ◽  
Alexander N. Timofeev
Keyword(s):  
Single Crystals ◽  
Point Defects ◽  
Diffusion Coefficients ◽  
Periodic Table ◽  
Secondary Ion Mass Spectrometry ◽  
Volume Diffusion ◽  
Bulk Diffusion ◽  
The Self ◽  
Self Diffusion ◽  
Secondary Ion

The bulk diffusion of homovalent non-magnetic atomic probes (APs) from the IVB group of the periodic table of elements (PTE) – Ti and Zr in tungsten single crystals was investigated by sec-tioning, using secondary ion mass spectrometry (SIMS). The Arrhenius dependences had the fol-lowing parameters: DWTi - (D0)WTi = (3.00.4 ) x 10-4 m2s-1, enthalpy QWTi = (576 ± 9) kJ/mole; DWZr - (D0)WZr = (2.3  0.6) x 10-4 m2s-1, QWZr = (561 9) kJ/mole. The measured parameters (D0,Q)WTi,Zr of diffusion of Ti and Zr atomic probes (APs) in W are in accord with the empirical correlation: the diffusion coefficients of the substitutional APs coincide with the self-diffusion coefficients in W at (Tm)W – its melting temperature. Enthalpies QWTi,Zr,Hf of the volume diffusion of homovalent non-magnetic APs of the IVB group of periodic table of elements (PTE) - Ti, Zr and Hf increase with the decrease of relaxation volumes of the complexes «vacancy-IVBAP» in W lattice. The energies (E)WvacIVBAP of elastic relaxation of the complexes «vacancy-IVBAP» in W lattice were estimated. Electron contributions EDN to the energies EWvacIVBAP of interaction of the point defects in complexes «vacancy-IVBAP» increase relative to value EWvacIIIBAP of interac-tion of the point defects in complexes «vacancy-IIIBAP» with the growth of d-electrons number in comparison with the complexes «vacancy-IIIBAP».

Measurement of growth rates for single crystals and pressed tablets of CuSO4.5 H2O on a rotating disc

1989 ◽  
Vol 54 (11) ◽  
pp. 2951-2961 ◽  
Author(s):  
Miloslav Karel ◽  
Jaroslav Nývlt
Keyword(s):  
Growth Rate ◽  
Single Crystal ◽  
Single Crystals ◽  
Growth Rates ◽  
Diffusion Coefficients ◽  
Preferred Orientation ◽  
Rotating Disc ◽  
Dissolution Rates ◽  
Rates Of Growth ◽  
Good Agreement

Measured growth and dissolution rates of single crystals and tablets were used to calculate the overall linear rates of growth and dissolution of CuSO4.5 H2O crystals. The growth rate for the tablet is by 20% higher than that calculated for the single crystal. It has been concluded that this difference is due to a preferred orientation of crystal faces on the tablet surface. Calculated diffusion coefficients and thicknesses of the diffusion and hydrodynamic layers in the vicinity of the growing or dissolving crystal are in good agreement with published values.

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