Sge. Te Velthuis et al., A three-dimensional model for the development of the microstructure in steel during slow cooling, MAT SCI E A, 277(1-2), 2000, pp. 218-228
A general three-dimensional model for the development of microstructure in
metals by diffusion-controlled processes has been constructed. The model ha
s been applied to the austenite (gamma-Fe) to ferrite (alpha-Fe) phase tran
sformation in plain-carbon steels. Starting from a Voronoi construction for
the austenite grains, the ferrite is assumed to nucleate at the corners of
the original austenite grains. Subsequently, the growth of the ferrite gra
ins is assumed to be radial and to fulfil the conditions of local equilibri
um at the ferrite-austenite interface. The development of the ferrite fract
ion, the ferrite grain size, and the number of active nucleation sites have
been evaluated as a function of time during continuous cooling. The influe
nce of the nucleation rate, the growth rate, the nucleus density, the cooli
ng rate, and the carbon concentration on the development of the microstruct
ure is discussed. (C) 2000 Elsevier Science S.A. All rights reserved.