Effect of Manganese Content on the as Cast Microstructure of Nodular ‎Cast Iron

In this research, the effect of manganese addition on the as cast microstructure of nodular ‎cast iron was investigated using experimental and simulation methods. For this purpose, ‎required cast sample with different manganese contents 0.5, 5, 11 and 17 wt.% were ‎produced in sand mold. The as cast microstructures were examined by optical microscopy ‎equipped by image analysis (MIP4 software) and hardness measurement. Then, using JMatPro ‎simulation software, the manganese segregation, the fraction, analysis and stability of the phase’s ‎at different temperature were predicted based on thermal analysis. The results showed that ‎the addition of manganese with 5, 11 and 17% weight percent has strongly affected the ‎solidification characterization, hardness, and morphology of graphite. A quantitative ‎evaluation of the graphite morphology showed that with increasing manganese content to ‎‎17 weight percent, the number of nodal counts and nodularity decrease 60 and 28 percent ‎respectively. The results of the JMatPro software showed that the M7C3 carbide is formed ‎alongside the ledeburitic composition. Also, the thermodynamically analysis of this software ‎revealed that manganese reduces the eutectic temperature and increases the solidification range.