Thixoformed grey cast iron microstructure characteristics
Keywords:
thixoforming, semisolid processing, grey cast iron, microstructural analysis.Abstract
A specific GCI (Fe-2.6o%wtC 1.5%wtSi) alloy for semisolid processing was designed and produced. Thixoforming tests were performed on the alloy at temperatures of 1160ºC and 1180ºC with retention times of 0, 30, 60 and 90 s. The analysis of the changes in the alloy microstructures upon completion of the thixoforming test revealed that the behavior of the stress required by the process was not significant for the retention times applied, specifically at 1 180 ºC. It was observed that graphite A changes to graphite B (or E) during the semisolid processing; however, it does not affect the interdendritic spacing between the graphite sheets. In addition, an increase in the liquid fraction decreases the stress required by the thixoforming process.Downloads
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