| Pub. Date | :Feb, 2019 |
|---|---|
| Product Name | : The IUP Journal of Mechanical Engineering |
| Product Type | : Article |
| Product Code | : IJME41902 |
| Author Name | : Rahul Basu |
| Availability | : YES |
| Subject/Domain | : Management |
| Download Format | : PDF Format |
| No. of Pages | : 13 |
A coupled set of equations describing heat and mass transfer during phase transformation is formulated incorporating surface convective effects. These equations, which are nonlinear due to the moving interface, are linearized and decoupled. The effects of the Biot, Fourier and Stefan numbers are analyzed through small parameter expansions. Solutions obtained via this artifice allow closer examination of surface effects on the boundary layer of the phase transformation. A relation is found on the effect of the glass transition temperature versus the boundary layer thickness for several alloys in various groups of the periodic table. Earlier work is analyzed in the light of the present analysis.
Klement et al. (1960) first reported amorphous alloys obtained by rapid quenching
(splat cooling), by the Duwez group at Caltech. Since then for about 30 years,
amorphous alloys were invariably formed as foils or thin ribbons, the formation of
bulk amorphous alloy remaining elusive. However, via the copper mold technique
(Inoue, 1999), it has been reported that amorphous alloys of macroscopic dimensions
(mm size) could be formed.
Chen (1980) reported that mm size samples were obtained by quenching. In
most of these, high cooling rates were essential to ‘freeze in’ the glassy structure.
Stefan numbers, Heat, Mass diffusion, Transient states, Quasi steady state analysis