DEPARTMENT OF MECHANICAL ENGINEERING

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Author: search.filters.author.Atanda, P.

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    Effect of silicon content and shake-out time on hardness and grain size properties of GL 250 cast iron
    (2011) Atanda, P.; Oluwadare, G.; Oluwole, O.
    "The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous casting practice variables such as shake-out time, pouring temperature, mould ambient conditions and inoculating technique. In this work, the effect of silicon content and shake-out time on the grain size (GS) and hardness properties of GL 250 cast iron was studied using a pouring temperature of 14000C and sand mould casting. Using charge materials consisting of pig iron and other additives, GL 250castings containing silicon contents of 1.7, 2.1 and 2.7% were casted using a constant pouring temperature of 14000C, molding sand of specified properties and ambient mould temperature of 320C. Results showed that type A flake type was obtained at 30mins shakeout time for all samples for the C.I composition under study. Increasing shake-out time decreased hardness and increased carbide grain size. Increasing silicon content was observed to increase grain size and reduce free graphite but with resultant decrease in hardness. Two mathematical relationships were derived. One related grain-size to silicon content and shakeout time while the second related Brinnel Hardness to Silicon content and shake-out time. They are: Grain Size=0.40 Si+0.17Shake-out Time-0.15 and BHN=-60.53Si-7.15Shake-out Time+329.35 at 14000C pouring temperature in a molding sand of specified properties and sand mould ambient temperature of 320C. "
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    Effect of silicon content and shake-out time on hardness and grain size properties of GL 250 cast iron
    (2011) Atanda, P.; Oluwadare, G.; Oluwole, O.
    "The properties of cast iron grade GL 250 are dependent on the microstructures developed during casting. These microstructures are in turn dependent on the composition of the alloy, type of mould and other numerous casting practice variables such as shake-out time, pouring temperature, mould ambient conditions and inoculating technique. In this work, the effect of silicon content and shake-out time on the grain size (GS) and hardness properties of GL 250 cast iron was studied using a pouring temperature of 14000C and sand mould casting. Using charge materials consisting of pig iron and other additives, GL 250castings containing silicon contents of 1.7, 2.1 and 2.7% were casted using a constant pouring temperature of 14000C, molding sand of specified properties and ambient mould temperature of 320C. Results showed that type A flake type was obtained at 30mins shakeout time for all samples for the C.I composition under study. Increasing shake-out time decreased hardness and increased carbide grain size. Increasing silicon content was observed to increase grain size and reduce free graphite but with resultant decrease in hardness. Two mathematical relationships were derived. One related grain-size to silicon content and shakeout time while the second related Brinnel Hardness to Silicon content and shake-out time. They are: Grain Size=0.40 Si+0.17Shake-out Time-0.15 and BHN=-60.53Si-7.15Shake-out Time+329.35 at 14000C pouring temperature in a molding sand of specified properties and sand mould ambient temperature of 320C. "
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    Microstructural study of heat treated chromium alloyed grey cast iron
    (2010) Atanda, P.; Okeowo, A.; Oluwole, O.
    "This work investigated the effect of annealing, normalizing and quenching heat treatments on the microstructure of some chromium alloyed grey cast iron. Three sets of ten samples each having chromium contents of 0.5, 1.5 and 2.5% were heat treated above the upper critical temperature, to austenitizing temperatures (800oC, 850oC, 900oC) for one hour each and then annealed, normalized and water quenched. Metallographic analyses of the heat treated samples were done. The results showed carbides content increased with increasing Chromium addition. "