Segregation streaks with sigma-phase - 1.4427
Segregations arises during the solidification of the steel, at the transition the phase from the liquid in the solid condition. Alloying elements and inclusions are enriched in the segregations. Positive and negative areas are existing in a segregation. The segregation distribution is dependent on different factors which positively or negatively influence the form. These factors are the casting temperature, casting rate, stirring parameter and cooling rate. In combination with segregations other negative microstructural influences can appear. Sigma-phase, which still is existing from the billet and wasn't dissolved at the heating and following hot forming, was found at this sample.
Rod wire 12,00 mm round - untreated