Hadfield steel used for railroad tracks was investigated for microstructural changes due to treatment regime. The steel was subjected to solution treatment by heating at a temperature of 1000ºC-1090ºC and then water quenched. The as-quenched material was then investigated for the development of microstructure in heating treatment at various temperatures (450ºC, 500ºC, 550ºC and 600ºC) and at two holding times (30min, 60min). The ensuing microstructure 
was then examined for morphology using Optical Computerize Microscopy ( as well as X-ray fluorescence spectroscopy (XRF) and fraction phase transform in that regime is also try to be calculated in point counting. Results of the morphological mapping showed that at lower temperatures, ferrites grow in the form of sheaves of parallel plates which nucleated at austenite grain surfaces. At a higher temperature, the ferrites gave way to acicular ferrite plates, growing in many different directions. A new phase was formed in the 400ºC to the 550ºC which was confirmed as to be the transformation amorph bainite to the accicular bainite. The upper threshold for pearlite formation was at 600ºC when again the ferritic structure was observed.
*Reza Fadhila, **Haftirman, ***Azwar Manaf *Che Husna Azhari
*The Department of Mechanical and Materials Engineering, Faculty of Engineering, Universiti Kebangsaan
**
*** The Department of Material Sciences, Post Graduated Study,
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