Title

The diffusion coefficient of scandium in dilute aluminum-scandium alloys

Document Type

Article

Publication Date

6-11-2014

Abstract

The diffusion coefficient of Sc in dilute Al-Sc alloys has been determined at 748 K, 823 K, and 898 K (475 °C, 550 °C, and 625 °C, respectively) using semi-infinite diffusion couples. Good agreement was found between the results of the present study and both the higher temperature, direct measurements and lower temperature, indirect measurements of these coefficients reported previously in the literature. The temperature-dependent diffusion coefficient equation derived from the data obtained in the present investigation was found to be D(m2/s)=(2.34±2.16)*10-4(m2/s)exp((-(167±6)(kJ/mol))/RT). Combining these results with data from the literature and fitting all data simultaneously to an Arrhenius relationship yielded the expression D(m2/s)=(2.34±0.84)*10-4(m2/s)exp((-(167±2)(kJ/mol))/RT). In each equation given above, R is 0.0083144 kJ/mol K, T is in Kelvin, and the uncertainties are ±1 standard error.

Publisher's Statement

© 2014 Springer Verlag. Publisher’s version of record: http://dx.doi.org/10.1007/s11661-014-2275-4

Publication Title

Metallurgical and Materials Transactions A