Influence of Semi-Solid Isothermal Heat Treatment on Microstructure of Gray Cast Iron

Naglaa Fathy

Department of Physics College of Science, University of Hail, Hail, Saudi Arabia.

DOI: 10.4236/jmmce.2013.16049                

Abstract

Materials serve as an enabling technology contributing to solutions in problems of concern to society. In this research, the effect of semi-solid isothermal heat treatment on graphite morphologies and matrix structure for gray cast iron were studied. Microstructure observations and measurements of flaky graphite morphology are reported as a function of isothermal heating time range of 5 to 25 minutes after isothermal heating temperature at 1163℃. The effect heating time, on the semisolid microstructures during partial re-melting was investigated. Flack graphite morphology was changed significantly by isothermal heating of gray cast iron at 1163℃ for heating time above 15 min resulting fine graphite morphology in matrix structure. Hardness increases with increasing heating time due to the amount of cementite and fine pearlite matrix for air cooled gray cast iron. The optimum heating treatment condition was achieved at the temperature of 1163℃ for the range of 15 to 20 min.

Keywords

Semi-Solid Heat Treatment; Isothermal; Gray Cast Iron; Microstructure

Conflicts of Interest

The authors declare no conflicts of interest.

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