Role of the Molar Volume on Estimated Diffusion Coefficients

Santra, Sangeeta; Paul, Aloke

doi:10.1007/s11661-015-2988-z

Cited by 23 publications

(6 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on our earlier investigations on heat-treated SS/TiTaNb explosive clads, an appreciable variation in molar volume with concentration is expected at temperatures beyond 700°C [4]. Sangeeta and Aloke Paul in a recent publication [13] have laid emphasis on incorporating the effect of molar volume for accurate determination of intrinsic diffusion coefficients in V 3 Ga system and have proposed the use of Wagner's method [14], when substantial molar volume change is involved during interdiffusion. However, the above methods are applicable for simple binary systems and there is difficulty in extending the same to multicomponent and multiphase systems, where diffusion of one element affects the other diffusing species.…”

Section: Introductionmentioning

confidence: 99%

Effect of alloying elements on interdiffusion phenomena in explosive clads of 304LSS/Ti–5Ta–2Nb alloy

2016

View full text Add to dashboard Cite

Dissimilar joints of 304L austenitic stainless steel (SS) and Ti-5Ta-2Nb alloy were fabricated using explosive cladding process with an aim to avoid the formation of brittle intermetallic phases at the interface. Subsequently, diffusion annealing heat treatments were carried out at temperatures in the range of 550-800°C for various durations. In the present study, concentration and temperature dependence of the distinct diffusion zones, formed at the clad interface, due to interdiffusion of the alloying elements, have been established using Electron Probe Micro Analysis and imaging of the interface. Molar volume showed a close match with the ideal Vegard's law at low temperatures while a non-linear negative deviation has been observed at high temperatures (800°C) due to the formation of secondary phases such as FeTi, Fe 2 Ti and bTi(Fe) phases. Interdiffusion parameters evaluated by Wagner's method showed sluggish diffusion kinetics of Fe and Ti at concentration corresponding to a two phase mixture of FeTi and Fe 2 Ti. Further, an attempt has been made to understand multicomponent diffusion using Dayananda's approach and estimation of effective interdiffusion coefficients revealed *22 lm shift of the interface from Matano plane at 800°C.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of alloying elements on interdiffusion phenomena in explosive clads of 304LSS/Ti–5Ta–2Nb alloy

2016

View full text Add to dashboard Cite

show abstract

“…Since the molar volume variation from one end to the other end of the diffusion couples Cu(8Sn)/Cu(8Ga) and Cu(8Sn)/Cu(8Si) is less than 5%, we consider a constant molar volume variation in our study. Based on our previous analysis on the effect of molar volume on estimated diffusion parameters, we know that this difference gives negligible difference in the estimated diffusion parameters [16]. Therefore, by neglecting molar volume variation (also means…”

mentioning

confidence: 98%

Estimation of intrinsic diffusion coefficients in a pseudo-binary diffusion couple

Santra

Paul

2015

Scripta Materialia

Self Cite

View full text Add to dashboard Cite

Major drawback of studying diffusion in multi-component systems is the lack of suitable techniques to estimate the diffusion parameters. In this study, a generalized treatment to determine the intrinsic diffusion coefficients in multi-component systems is developed utilizing the concept of pseudo-binary approach. This is explained with the help of experimentally developed diffusion profiles in the Cu(Sn, Ga) and Cu(Sn, Si) solid solutions.Estimation of the diffusion coefficients following the conventional approach in a binary system implementing the diffusion couple technique is rather straightforward. It is a stringent process in a ternary system and impossible in multi-component systems [1]. As an alternate approach, the concept of the average effective interdiffusion coefficient was introduced by Dayananda and Sohn [2]. This is a kind of average interdiffusion coefficient of the main and cross interdiffusion coefficients over a wide composition range. Much recently, Chen et al. [3] proposed a method to 2 1 * * * *

show abstract

“…One was proposed by Wagner with respect to composition normalized variable after considering the molar volume variation and another one was proposed by den Broeder with respect to the concentration normalized variable. Although, it is known to produce different values of the interdiffusion coefficient depending on the molar volume variation [24], the choice of a method by a particular research group is rather random. Incidentally both the methods were published in the same year 1969.…”

Section: Resultsmentioning

confidence: 99%

Development of different methods and their efficiencies for the estimation of diffusion coefficients following the diffusion couple technique

Baheti

Paul

2018

Acta Materialia

Self Cite

View full text Add to dashboard Cite

The interdiffusion coefficients are estimated either following the Wagner's method expressed with respect to the composition (mol or atomic fraction) normalized variable after considering the molar volume variation or the den Broeder's method expressed with respect to the concentration (composition divided by the molar volume) normalized variable. On the other hand, the relations for estimation of the intrinsic diffusion coefficients of components as established by van Loo and integrated diffusion coefficients in a phase with narrow homogeneity range as established by Wagner are currently available with respect to the composition normalized variable only. In this study, we have first derived the relation proposed by den Broeder following the line of treatment proposed by Wagner. Further, the relations for estimation of the intrinsic diffusion coefficients of the components and integrated interdiffusion coefficient are established with respect to the concentration normalized variable, which were not available earlier. The veracity of these methods is examined based on the estimation of data in Ni-Pd, Ni-Al and Cu-Sn systems. Our analysis indicates that both the approaches are logically correct and there is small difference in the estimated data in these systems although a higher difference could be found in other systems. The integrated interdiffusion coefficients with respect to the concentration (or concentration normalized variable) can only be estimated considering the ideal molar volume variation. This might be drawback in certain practical systems.

show abstract

Role of the Molar Volume on Estimated Diffusion Coefficients

Cited by 23 publications

References 17 publications

Effect of alloying elements on interdiffusion phenomena in explosive clads of 304LSS/Ti–5Ta–2Nb alloy

Effect of alloying elements on interdiffusion phenomena in explosive clads of 304LSS/Ti–5Ta–2Nb alloy

Estimation of intrinsic diffusion coefficients in a pseudo-binary diffusion couple

Development of different methods and their efficiencies for the estimation of diffusion coefficients following the diffusion couple technique

Contact Info

Product

Resources

About