A 2-D nucleation-growth model of spheroidal graphite

Jacques Lacaze (1) , Jacques Bourdie (1, 2) , Manuel Jesus Castro-Román (3)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 Saint-Gobain
3 CINVESTAV - Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional

Analysis of recent experimental investigations, in particular by transmission electron microscopy, suggests spheroidal graphite grows by 2-D nucleation of new graphite layers at the outer surface of the nodules. These layers spread over the surface along the prismatic direction of graphite which is the energetically preferred growth direction of graphite when the apparent growth direction of the nodules is along the basal direction of graphite. 2-D nucleation-growth models first developed for precipitation of pure substances are then adapted to graphite growth from the liquid in spheroidal graphite cast irons. Lateral extension of the new graphite layers is controlled by carbon diffusion in the liquid. This allows describing quantitatively previous experimental results giving strong support to this approach.

Mots clés: Spheroidal graphite; Cast iron; 2-D nucleation; Lateral growth

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Génie des procédés; Matériaux

Jacques Lacaze, Jacques Bourdie, Manuel Jesus Castro-Román. A 2-D nucleation-growth model of spheroidal graphite. Acta Materialia, 2017, vol. 134, pp. 230-235. ⟨10.1016/j.actamat.2017.05.032⟩. ⟨hal-01580469⟩