Browsing by Author "Omotoyinbo, J. A."

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Effect of thermomechanical working on the strengthening of some austenitic steel grades
(Elsevier, 2009) Omotoyinbo, J. A.; Oluwole, O. O.
"This work studied the effects of degrees of warm-split rolling at different temperatures on the strengths of three different grades of austenitic steels (chrome–manganese, chrome–manganese with Ni and Mo additions, chrome–nickel with Mn and Mo additions). The results were compared with cold-rolling effects on the steel grades. The tensile, hardness and impact strengths of the rolled products were obtained. The results showed that thermomechanical working remarkably influenced the properties of the alloys. The trend in property change was dictated by both the degree and temperature of deformation. It was concluded that warm deformation at 350 _C and degree of deformation between 20% and 30% enhanced the plasticity values (toughness and ductility) of the alloys. "
Working properties of some selected refractory clay deposits in South Western Nigeria
(2008) Omotoyinbo, J. A.; Oluwole, O. O.
"Working properties of some clay deposits in Ekiti State, Nigeria were investigated with a view to determine their suitability for use as refractory bricks. The samples were collected from three different commercial pottery clay centers in Ekiti State; they are Ara, Awo and Isan. Two varieties were collected from both Ara and Isan, which are named Ara 1, Ara 2, and Isan 1, Isan 2 respectively while only one type was collected from Awo. The clay samples were crushed, pulverized, sieved and their chemical compositions were determined. The clay samples were treated separately as well as blended together in different proportions and moulded into bricks. The bricks were dried and fired to 1050°C. Tests for refractoriness, thermal shock resistance, shrinkage, thermal expansion; bulk density, porosity, and compressive strength were carried out on each batch specimen. The results showed that Ara 2 and Ara 1, 2 combined in equal proportions displayed the highest thermo chemical stability. They also possess comparatively high cold crushing strength, and high thermal shock resistance, but definitely not the highest. The apparent porosity of all the batch specimens was found to be high as well as the bulk densities, while the shrinkage of all the specimens were low. It was concluded that 100% Ara 2, and a blend of Ara 1 and 2 in equal proportions, are most suitable for production of crucibles, and furnace lining for non ferrous metals processing, such as Aluminium, Lead and Bronze. "