1997 Volume 37 Issue 4 Pages 332-338
Effect of titanium addition on the size and dispersion of MnS inclusions in Fe-0.1C-1Mn-0.02S(mass%) base alloys has been investigated by microscopy. Titanium addition brings about a marked decrease in the size of MnS inclusions which are otherwise large and globular in Ti-free specimens. The formation mechanism of MnS inclusions is discussed on the basis of phase diagram information and thermodynamics of particle engulfment during solidification. It is shown that the reduction in size of the MnS particles consequent on Ti addition is directly the result of successive nucleation events involving (Ti, Mn)O and MnS at the solid/liquid interface of iron.