Particle Evolution and Grain Growth during Annealing of a Complex Multiphase Al-Sn Triboalloy
A fine microstructure stabilised by dispersed particles is an interesting option for increasing the resistance of Al-Sn tribo-alloys without sacrificing ductility. Particle stimulated and continuous recrystallisation allow achieving this goal, but require careful preconditioning of the microstructure to obtain the desired particle distribution. As-cast slabs of Al 12%Sn2%Pb3%Si contain large plates of b-AlFeSi and modified silicon in an aluminium matrix. Sn forms a reticular network which is liquid at conventional annealing temperatures. Experiments show that metastable b-AlFeSi initially coarsens due to Ostwald ripening, but later dissolves and the remainder transforms into FeSiAl12. Silicon partitions to the liquid, allowing the nucleation of numerous small Si-grains.
B. Bacroix, J.H. Driver, R. Le Gall, Cl. Maurice, R. Penelle, H. Réglé and L. Tabourot
S. M. Cerrud et al., "Particle Evolution and Grain Growth during Annealing of a Complex Multiphase Al-Sn Triboalloy", Materials Science Forum, Vols. 467-470, pp. 963-968, 2004