Effect of Mn and Si addition on microstructure and tensile properties of cold-rolled and annealed pearlite in eutectoid Fe-C alloys

The microstructures and tensile properties of cold-rolled and annealed pearlite in Fe-0.8mass%C alloys with various contents of Mn and Si were investigated. With the addition of Mn and Si, the tensile strength (TS) and yield strength (YS) of cold-rolled and annealed pearlite were vastly improved, but its effect on ductility of the cold-rolled pearlite is negligible. The addition of Si is quite effective in improving the ductility of cold-rolled and annealed pearlite, especially when the strength is at a higher level, i.e., lower annealing temperature or shorter annealing period. The optimal tensile properties in the alloys with Mn or Si were obtained after annealing at 723 K for short annealing periods (30 to 120s). The combined addition of Mn and Si is more effective in improving the tensile properties of cold-rolled and annealed pearlite.