Department of Mechanical Engineering

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    Effect of copper addition and solution heat treatment on the mechanical properties of aluminum alloy using formulated bio-quenchant oils
    (Engineering and Applied Science Research, 2020-01-01) Adekunle A.S.; Adekunle Akanni Adeleke; Peter Pelumi Ikubanni; Omoniyi P. O.; Gbadamosi T. A.; Jamiu Kolawole Odusote
    Addition of copper and use of solution heat treatment solution with bio degradable vegetable oils as quenchants has great potential to improve the mechanical properties of aluminum and its alloys. In this study, copper was added to as-received Al- Si-Mg alloy to produce Al-Si-Cu-Mg alloy. The specimens were quenched with blended bleached bio-quenchant oils and a petroleum-based oil after solution heat treatment. The alloy was heat treated at 500℃, soaked for 20 minutes in a muffle furnace before quenching in the formulated bio-quenchant oils. The cooling properties, mechanical properties and microstructure of the solution treated specimens were determined. Blended bleached melon (BBM) oil was observed to have offered a higher cooling rate of 49.3 ℃ s-1 compared to the petroleum-based (PB) oil with a cooling rate of 25.8 ℃ s-1. Blended bleached melon oil exhibited the highest quench severity value of 1.0074 m-1, while petroleum-based oil was 0.6133 m-1. The as-received alloy and as-cast alloy specimens exhibited tensile strength values of 125.33 and 131.37 N mm-2, respectively, while a higher tensile strength value of 139.30 Nmm-2 was obtained using the blended bleached melon oil. The highest Rockwell hardness number, 61.00 HRB, was obtained using blended bleached melon oil. The overall mechanical properties of specimens improved after the addition of copper and heat treatment in various bio-quenchant oils
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    A COOLING POTENTIAL OF FORMULATED BIO-QUENCHANT OILS ON A CAST ALUMINIUM ALLOY MATERIAL
    (Journal of Chemical Technology and Metallurgy,, 2020-02-02) Adebayo Surajudeen Adekunle; Adekunle Akanni Adeleke; Tajudeen Adelani Gbadamosi; Friday O. Nwosu; Jamiu Kolawole Odusote; Peter Olorunleke Omoniyi; Tajudeen O. Popoola; Kazeem Adekunle Adebiyi
    The biodegradable vegetable oil based quenchants can serve as cooling media alternative to that of the toxic non-biodegradable petroleum based mineral oil in a heat treatment of aluminium and its alloy. 70 vol. % of edible vegetable oil are blended with 30 vol. % of Jatropha oil to form bio-quenchant oils for Aluminium (Al)-alloy probe treated at 500oC and soaked for 15 min in a muffle furnace. The cooling potential properties such as the cooling rate, the heat transfer coefficient, the Grossman quench severity and the biot number are investigated. The results obtained show that the blended bleached (BB) melon oil provides the highest cooling rate of 49.30oC s-1, while the blended raw (BR) palm oil ensures the lowest cooling rate of 18.45oCs-1. Heat transfer coefficients of 704.6 Wm-2K-1, 432.3 Wm-2K-1, and 394.4 Wm-2K-1 are exhibited by the blended bleached melon oil, the blended raw melon oil and the blended bleached groundnut oil, respectively. They are found higher than that of a petroleum based mineral oil, which amounts to 68.7 Wm-2K-1. The lowest heat transfer coefficient of 272.11 Wm-2K-1 is obtained in case of using a blended raw palm oil. The quench severity of the blended bleached melon oil, the blended raw melon oil and the blended raw groundnut oil refers to a Grossman H-factor of 1.01 m-1, 0.78 m-1, and 0.67 m-1, respectively. The latter values are higher than that obtained in case of a blended raw palm oil, which is equal to 0.37 m-1. However, the heat flow parameters obtained reveal that the blended bleached and the blended raw melon and groundnut oil can be characterized as fast quenching oils, while the blended bleached and the blended raw palm oil can be characterized as medium quenching oils of results comparable to and even better than those of the industrial petroleum based mineral oil.