Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
(OP)
Hello folks, I am having problems to find de the self-diffusion coefficients of Cr and of Nb.
Does anyone have these numbers with reference ?
Thank you a lot for your time to answer me,
Maleck
Does anyone have these numbers with reference ?
Thank you a lot for your time to answer me,
Maleck





RE: Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
http
RE: Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
Anyway, I did not know this site and it can be very useful since it resumes many parts of the book. Having a electronic version saves a lot of space :) and it weights nothing :)
The other users can have the 18 chapters in their hard-drives browsing the pages :
http://thayer.dartmouth.edu/~defmech/chapter_1.htm
http://thayer.dartmouth.edu/~defmech/chapter_2.htm
(...)
h
Anyway, if someone has the value of the self-difusion of chromium into chromium and that of niobium into niobium (with reference), it would be great !
Thank you again,
Maleck
RE: Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
The self diffusion parameters for Cr/Cr and Nb/Nb are as follows;
Element Tm Do Q
(K) (M^2S^-1) (Kj/mol)
x 10^4
Cr 2130 1280 441.9
Nb 2740 0.524 395.6
D = Do exp((-Q)/RT)
Note Do value is multiplied by X10^4 to obtain (cm^2s^-1)
Source; Physical Metallurgy Handbook, Sinha
pages 2.44 and 2.45
RE: Self-diffusion coefficients (CHROMIUM ? NIOBIUM ?)
Cheers,
Maleck