Microstructure and mechanical properties of ferromanganese-silicon alloys

The structure of the alloy plays a significant role in determining its properties. In the present study, the Fe-Mn-Si alloys were synthesized using ferromanganese (FeMn) and ferrosilicon (FeSi) lumps. The lump materials were crushed and sieved to obtain small granules. It was then wet-milled into a fine powder using a shaker mill for 4h. In order to obtain a homogeneous mixture, the FeMn and FeSi powders with the composition of 50(FeMn)-50(FeSi), 75(FeMn)-25(FeSi) and 87.5(FeMn)-12.5(FeSi) were mechanically alloyed for 2h. The mixed powder was compacted at 8 ton in load and then sintered in a vacuum furnace at 1100°C for 2h. The shrinkage and density of sintered alloy increase with the increase of Mn and the decrease of Si content in the alloy. The results also show that pores and oxide are formed in the alloy. Their fraction is likely to decrease with decreasing Si concentration. According to the results of hardness measurement, the 75(FeMn) alloy with 25(FeSi) content show the highest hardness among the other compositions. The obtained results were intensively discussed in this paper.