Solidification of austenitic stainless steels

As steelmakers are required to produce increasingly highly alloyed stainless steels, it becomes imperative to be able to predict the solidification characteristics of these steels, In this study the solidification structures of small laboratory ingots with various Ni, Cr, Si, Mo, and N contents are compared with predictions from both empirical and thermodynamic techniques (MTDATA), Use of the comprehensive MTDATA package resulted in accurate predictions of the primary phase for most of the steels, Slightly less accurate predictions were obtained using a ternary version of MTDATA, or empirically with a recently revised phase diagram. Predictions from these latter methods can be expressed graphically, suitable for a rapid initial assessment of solidification mode, The more rigorous technique is recommended for borderline compositions only. The residual ferrite content can be predicted with reasonable accuracy using traditional techniques, The results have been used to determine suitable compositions for continuous casting trials for a range of steel grades.