Self-Diffusion and Impurity Diffusion in Actinide Metals

Neumann, Gerhard; Tuijn, C.

doi:10.1016/s1470-1804(08)00010-2

Cited by 123 publications

(183 citation statements)

References 22 publications

Supporting

Mentioning

155

Contrasting

Unclassified

Order By: Relevance

“…Studies of impurity diffusion for tungsten in nickel and cobalt generally show that, over the range of ageing temperatures in this study, that the diffusivity of tungsten is greater in cobalt than in nickel [38,39], Figure 9(a). This suggests that addition of nickel may lower the diffusivity of tungsten.…”

Section: Discussionmentioning

confidence: 82%

“…(a) Variation of tungsten diffusivity in nickel and cobalt over the approximate temperature range investigated in this study. [38,39];(b) Coarsening rate constants normalised by the absolute coarsening temperatures and the γ/γ lattice misfit, δ, plotted against the mean structural interface gradient widths measured using HAADF STEM. ;(c) Coarsening rate constants K normalised for the three alloys normalised by the absolute annealing temperatures and tungsten diffusivity at those temperatures.…”

Section: Alloymentioning

confidence: 99%

See 1 more Smart Citation

Coarsening behaviour and interfacial structure of γ′ precipitates in Co-Al-W based superalloys

Vorontsov¹,

Barnard

Rahman³

et al. 2016

Acta Materialia

View full text Add to dashboard Cite

This work discusses the effects of alloying on the coarsening behaviour of the L1 2 ordered γ phase and the structure of the γ/γ interfaces in three Co-Al-W base superalloys aged at ∼90 • C below the respective solvus temperatures: Co-7Al-7W, Co10Al-5W-2Ta and Co-7Al-7W-20Ni (at.%). The coarsening kinetics are adequately characterised by the classical Lifshitz-Slyozov-Wagner model for Ostwald ripening. Co-7Al-7W exhibited much slower coarsening than its quaternary derivatives. Alloying can be exploited to modify the coarsening kinetics either by increasing the solvus temperature by adding tantalum, or by adding nickel to shift the rate controlling mechanism towards dependence on the diffusion of aluminium rather than tungsten. Lattice resolution STEM imaging was used to measure the widths of the order-disorder (structural) and Z-contrast (compositional) gradients across the γ/γ interfaces. Similarly to nickel base superalloys, the compositional gradient was found to be wider than the structural. Co-7Al-7W-20Ni had much wider interface gradients than Co-7Al-7W and Co-10Al-5W-2Ta, which suggests that its γ phase stoichiometry is less constrained. A possible correlation between temperature and misfit normalised r vs. t 1 3 coarsening rate coefficients and the structural gradient width has also been identified, whereby alloys with wider interfaces exhibit faster coarsening rates.

show abstract

Section: Discussionmentioning

confidence: 82%

Section: Alloymentioning

confidence: 99%

Coarsening behaviour and interfacial structure of γ′ precipitates in Co-Al-W based superalloys

Vorontsov¹,

Barnard

Rahman³

et al. 2016

Acta Materialia

View full text Add to dashboard Cite

show abstract

“…Therefore, this material would not be considered for experiments with Lv. The peculiarly long adsorption times on Y are already reported in [15,29]. Generally, adsorption times of 5 ms or less are common for adsorption enthalpies of −250 kJ/mol at 1750 K. The kinetic description of segregation is closely related to diffusion coefficients.…”

Section: Calculationsmentioning

confidence: 74%

“…Therefore, diffusion coefficients of transactinides in various metallic host matrices have to be • Host given for tungsten as host material at its melting temperature (θ = 1.00), for details see text. The circles are data from Neumann [15], triangles from Beyer et al [14], and squares from Wittwer et al [16], respectively. The hollow rectangles with the error bars The volume approach can be used to predict the diffusion coefficients of SHE at certain relative temperatures if the molar volume of the SHE in the host material can be predicted.…”

Section: Calculationsmentioning

confidence: 99%

“…Because the SHE in focus have quite short half-lives in the order of single seconds or even less, the release process must be very fast. This work provides information, which materials are best suited for this task, using available diffusion and release data [14][15][16]. Based on Einstein's diffusion formula it can be calculated that at least diffusion coefficients of 1 × 10 −8 cm 2 s −1 must be reached in the catcher material to provide quantitative release from 2 μm thick foils within 0.5 s. Foils of 2 μm thickness represent a good compromise between fast release and technical applicability.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Prediction of the thermal release of transactinide elements (112 ≤Z≤ 116) from metals

Wittwer¹,

Dressler

Eichler³

et al. 2013

Radiochimica Acta

View full text Add to dashboard Cite

Summary. Metallic catcher foils have been investigated on their thermal release capabilities for future superheavy element studies. These catcher materials shall serve as connection between production and chemical investigation of superheavy elements (SHE) at vacuum conditions. The diffusion constants and activation energies of diffusion have been extrapolated for various catcher materials using an atomic volume based model. Release rates can now be estimated for predefined experimental conditions using the determined diffusion values. The potential release behavior of the volatile SHE Cn (E112), E113, Fl (E114), E115, and Lv (E116) from polycrystalline, metallic foils of Ni, Y, Zr, Nb, Mo, Hf, Ta, and W is predicted. Example calculations showed that Zr is the best suited material in terms of on-line release efficiency and long-term operation stability. If higher temperatures up to 2773 K are applicable, tungsten is suggested to be the material of choice for such experiments.

show abstract

First‐principles Study of Diffusion Coefficients of Alloy Elements in Dilute Mg Alloys

Zhou¹,

Shang²,

Wang³

et al. 2016

Magnesium Technology 2016

View full text Add to dashboard Cite

Self-Diffusion and Impurity Diffusion in Actinide Metals

Cited by 123 publications

References 22 publications

Coarsening behaviour and interfacial structure of γ′ precipitates in Co-Al-W based superalloys

Coarsening behaviour and interfacial structure of γ′ precipitates in Co-Al-W based superalloys

Prediction of the thermal release of transactinide elements (112 ≤Z≤ 116) from metals

First‐principles Study of Diffusion Coefficients of Alloy Elements in Dilute Mg Alloys

Contact Info

Product

Resources

About