Kc. Russell et Fh. Froes, EFFECTS OF COMPOSITION ON ISOTHERMAL SOLIDIFICATION KINETICS OF HIGHLY UNDERCOOLED ALLOYS, Materials science & engineering. B, Solid-state materials for advanced technology, 32(3), 1995, pp. 279-284
A modified theory incorporates the effects of composition on homogeneo
us nucleation and isotropic crystal growth in isothermal, massive soli
dification of alloys. Simple, realistic values for the needed kinetic
and thermodynamic quantities facilitate calculation of grain size and
solidification times as a function of temperature and concentration. R
easonable agreement is found between the isothermal theory and results
of continuous cooling experiments on pure Al and some Al-based alloys
. The conditions for producing a vitreous, non-crystalline solid are a
lso given. We propose that the extremely fine grain sizes obtained in
AL-Ge and Ag-Cu alloys rise from quenching to form a glass, followed b
y isothermal crystallization at or near room temperature.