5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

Deleterious effect of sulphur excess in gray iron is shortened by Mn addition. The suitable Mn addition according to sulphur in the metal is preformed according to the different addition rules available in open literature. With Mn addition is intended to avoid FeS formation by MnS precipitation that also prevents the undesirable effect of sulphur dissolved in the melt in the morphology of graphite flakes. To achieve the latter effect, it is thinking that MnS precipitation must occurs before eutectic reaction were flakes of graphite are formed. In order to get more basis for the choice of the rule of Mn addition, this study was focused to provide experimental evidence of MnS precipitation sequence in a hypoeutectic gray iron; Fe-3.3%C-2%Si-0.012P with 6 different Mn/S ratios: 28, 16, 4, 4.6, 2.6 and 0.7. Partially solidified samples of these alloys were obtained using a Bridgman furnace with quenching capabilities. Experimental evidence shown that the temperature of precipitation of MnS is in a reasonable agreement with the temperatures that could be calculated using thermodynamic data extrapolated from 1600 °C.