Dependence of Diffusion Paths on Thermodynamic Factors in Ternary Systems

2008 ◽  
Vol 277 ◽  
pp. 119-124 ◽  
Author(s):  
Ü. Ugaste ◽  
J. Priimets ◽  
Tony Laas
Keyword(s):  
Approximate Equation ◽  
Ternary Systems ◽  
Diffusion Path ◽  
Tracer Diffusion ◽  
Diffusion Paths ◽  
Slope Function ◽  
Experimental Values ◽  
The Impact ◽  
Tracer Diffusion Coefficients ◽  
Thermodynamic Factors

The impact of thermodynamic factors on deviation from linearity of diffusion path in the ternary system Cu-Fe-Ni is analyzed. For that the slope function of the diffusion path for the diffusion couples 65Ni30Cu5Fe –29.5Ni16.5Cu54Fe, 49.5Ni50.5Fe – 51Ni49Cu and 84Cu16Ni – 50Ni50Fe, annealed at 1000°C for 196h, were calculated by an approximate equation using only thermodynamic data. Results of the calculation were compared with the values of the slope function obtained directly from experimental data. It is shown that despite of the fact that the tracer diffusion coefficients of the components in the system Cu-Fe-Ni are not equal the coincidence between the calculated and experimental values of the slope function is remarkable. This allows us to conclude that at least in this case the deviation of the diffusion path from linearity depends mainly on the thermodynamic properties of the system.

The Influence of Thermodynamic Properties of Alloys on Effective Interdiffusion Coefficients in Ternary Systems

2007 ◽  
Vol 263 ◽  
pp. 141-146 ◽  
Author(s):  
Ü. Ugaste ◽  
Tony Laas ◽  
T. Škled-Gorbatšova
Keyword(s):  
Thermodynamic Properties ◽  
Diffusion Coefficients ◽  
Reasonable Agreement ◽  
Ternary Systems ◽  
Tracer Diffusion ◽  
Diffusion Couples ◽  
Experimental Values ◽  
Tracer Diffusion Coefficients ◽  
Interdiffusion Coefficients ◽  
The Relationship

To prove the validity of Dayananda’s phenomenological model of interdiffusion in ternary systems the effective interdiffusion coefficients for a few diffusion couples in the system Cu-Ni-Fe, annealed at 1000 oC, are calculated on the basis of this model using available tracer diffusion and thermodynamic data. It is found that the calculated values of effective interdiffusion coefficients are in reasonable agreement with experimental values extracted independently from experimental concentration--penetration curves. Using the relationship between effective interdiffusion coefficients, tracer diffusion coefficients and thermodynamic factors, it is shown that thermodynamic properties of alloys play a significant role in interdiffusion processes in the system Cu-Fe-Ni.

Thermodynamic Aspects of Diffusion Paths in Ternary Systems

2007 ◽  
Vol 263 ◽  
pp. 135-140 ◽  
Author(s):  
Tony Laas ◽  
Ü. Ugaste ◽  
J. Priimets
Keyword(s):  
Thermodynamic Properties ◽  
Ternary Systems ◽  
Diffusion Path ◽  
Experimental Investigations ◽  
Ideal System ◽  
Diffusion Paths ◽  
Interdiffusion Coefficients ◽  
The Relationship ◽  
And Diffusion ◽  
Specific Influence

Description of diffusion paths is one of the most interesting and topical problems in experimental investigations of interdiffusion in multicomponent systems and, particularly, in ternary systems. The relationship between effective interdiffusion coefficients and diffusion paths in ternary systems has been discussed earlier but the specific influence of the mobility and thermodynamic properties of components on the characteristics of the diffusion path is still unclear. In this paper an attempt is made to clarify the separate influences of mobility and thermodynamics on the behavior of diffusion paths in ternary systems and the corresponding correlation is found. It is shown that in most cases the deviation of the diffusion path from linearity (an ideal system) is related to the deviation of the thermodynamic properties from the ideal. The results obtained are analyzed on the basis of thermodynamic data for the ternary system Cu-Fe-Ni.

The Effective Interdiffusion Coefficients in Experimental Investigations of Interdiffusion in Ternary Systems

2005 ◽  
Vol 237-240 ◽  
pp. 121-126 ◽  
Author(s):  
Ü. Ugaste
Keyword(s):  
Diffusion Couple ◽  
Ternary Systems ◽  
Diffusion Path ◽  
Experimental Investigations ◽  
Ternary Diffusion ◽  
Ternary Diffusion Couple ◽  
Interdiffusion Process ◽  
Variable Diffusion ◽  
Diffusion Paths ◽  
Interdiffusion Coefficients

The application of the effective interdiffusion coefficients for describing the interdiffusion process in ternary systems is discussed. It is shown that the relative values of effective interdiffusion coefficients, which are directly related to the diffusion path developed in a given diffusion couple, are responsible for deviation of the diffusion paths from linearity. The relationship between effective interdiffusion coefficients and partial (intrinsic) coefficients in ternary systems is analysed. It is shown that Boltzmann’s solution for diffusion equation with variable diffusion coefficient by means of relatively easy calculation procedure gives reliable results for the calculation concentration distributions in a ternary diffusion couple.

scholarly journals Research on the Influencing Factors of Brand Diffusion via Social Media

2020 ◽  
Vol 189 ◽  
pp. 03032
Author(s):  
Peng Yunan ◽  
Wang Zongshui ◽  
Zhang Jian
Keyword(s):  
Social Media ◽  
Diffusion Path ◽  
Impact Factors ◽  
Audience Participation ◽  
Factors Influencing ◽  
Diffusion Paths ◽  
Main Factors ◽  
The Impact ◽  
And Diffusion ◽  
Content Information

[Purpose] The paper aims to identify the impact factors of brand diffusion via social media. It provides a theoretical reference for enterprises to choose social media and improves brand influence. [Method] First, we summarize the general path of brand diffusion through social media by studying the relevant literatures. Next, four popular social media WeChat, Weibo, Tiktok, and Taobao have been selected as research samples to analyze the different brand diffusion paths. Finally, we summarize the impact of brand diffusion on social media according to the paths. [Results] The result shows that the main factors influencing brand diffusion on social media are diffusion content, information credibility, audience participation, and diffusion path.

Calculating of Diffusion Paths in Ternary Systems Using Effective Interdiffusion Coefficients of Components

2005 ◽  
Vol 237-240 ◽  
pp. 1264-1269 ◽  
Author(s):  
J. Priimets ◽  
A. Ainsaar ◽  
Ü. Ugaste
Keyword(s):  
Interdiffusion Coefficient ◽  
Good Accuracy ◽  
Ternary Systems ◽  
Diffusion Path ◽  
Correct Choice ◽  
Diffusion Couples ◽  
Practical Application ◽  
Strong Deviation ◽  
Diffusion Paths ◽  
Interdiffusion Coefficients

The peculiarities of practical application of effective interdiffusion coefficients of components for calculating diffusion paths in ternary systems are analysed. It is shown that infinite values of the interdiffusion coefficients at zero concentration gradient’s points do not remarkably affect the accuracy of calculation in the case of a correct choice of variables. At zero-flux planes where the respective effective interdiffusion coefficient is equal to zero, no calculation problems arise, as evidently zero-flux planes can occur simultaneously only for one of the components. The results of calculation of diffusion paths for diffusion couples in the ternary systems Cu-Fe-Ni and Co-Fe-Ni using respective effective interdiffusion coefficients are presented. These results demonstrate a good accuracy of such kind of calculations even in the case of very strong deviation from linearity of the diffusion path.

Non-Stoichiometry and Cation Tracer Diffusion Studies in the Magnetite-UlvÖSpinel Solution, (Fe,Ti)3-δO4

1994 ◽  
Vol 369 ◽  
Author(s):  
Sanjeev Aggarwal ◽  
Rudiger Dieckmann
Keyword(s):  
Diffusion Coefficients ◽  
Tracer Diffusion ◽  
Oxygen Activity ◽  
Spinel Solid Solution ◽  
Low Oxygen ◽  
Cation Diffusion ◽  
Deviation From Stoichiometry ◽  
Diffusion Studies ◽  
Tracer Diffusion Coefficients ◽  
Point Defect Structure

AbstractCation diffusion in the spinel solid solution (Fe1-xTix)3-δO4 (0≤ x ≤ 0.3) was investigated at 1200 ºC as a function of oxygen activity, aO2 and cationic composition, x. At different cationic compositions, cation tracer diffusion coefficients, D*Me of Me = Fe and Ti were measured as a function of oxygen activity. Plots of log DMe vs. loga0 show V-shaped curves, indicating that different types of point defects prevail at high anc low oxygen activities. Thermogravimetric experiments were conducted, using a high resolution microbalance, to determine the deviation from stoichiometry in (Fe1-xTix)3-δO4 at 1200 °C. δversus log aO2 curves are S-shaped. An analysis of the oxygen activity dependences of thecation diffusion coefficients and the deviation from stoichiometry with regardto the point defect structure suggests that at high oxygen activities cation vacancies are the predominant defects governing the deviation from stoichiometry and the diffusion ofcations. At low oxygen activities, and at small values of x, cation interstitials determine the deviation from stoichiometry, while they dominate for 0 ≤ x ≤ 0.3 inthe cation diffusion.

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