Faculty of Engineering
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Item Understanding casting behaviour of low carbon high manganese steel through detailed characterization of mould powder and mould top slag(Taylor and Francis, 2023-02-02) D. Paswan; J. K. Ansu; Adekunle Akanni Adeleke; Peter Pelumi Ikubanni; C. T. Christopher; T. K. Roy; P. Palai; M. MalathiThis study focused on multistage characterization techniques in developing an understanding of the abnormal casting behaviour of low carbon high manganese (LCHMn) steel. In addition to raw mould powder used for casting LCHMn steel, mould top slag samples were also collected for normal and abnormal casting conditions. Raw mould powder and top slag samples were characterized using XRF, XRD, and SEM-EDS to determine chemical composition, crystallinity and morphology. The chemical composition results revealed deviation of normal and abnormal behaviours from the mould powder due to the pickup of oxides of Al, Mn, and Ti. The SEM analyses of raw mould powder showed different granular particle sizes while pores and glassy/crystalline structure were seen for normal and abnormal behaviour at casting. CaF2, CaSiO3, and Na2CaSi3O9 were revealed as the mineralogical phases. There was a modified crystalline phase present in the abnormal behaviours at casting due to pickup of other oxides.Item Evaluation of thermal decomposition characteristics and kinetic parameters of melina wood(Taylor and Francis, 2019-08-06) Adekunle Akanni Adeleke; J. K. Odusote; O. A. Lasode; Peter Pelumi Ikubanni; M. Madhurai; D. PaswanThe evaluation of thermal decomposition characteristics and kinetic parameters of melina wood were investigated. Proximate, ultimate and calorific value analyses of the melina wood were carried out based on standards. Melina wood was subjected to multiple heating rates (5–15 C/min) in thermogravimetric experiment. Two prominent isoconversional methods (Flynn-Wall-Ozawa and Starink) were adopted to obtain kinetic parameters from the non-isothermal thermogravimetric analysis curves. The ash, volatile matter and carbon contents of the melina were 2.15, 81.42 and 47.05%, respectively, while the calorific value was 18.72 MJ/kg. The main devolatilization stage of melina ranged from 220 C to 350 C while 80% weight loss was obtained below 400 C. The activation energy varied between approximately 15 and 162 kJ/mol as a function of degree of conversion. The pre-exponential factors varied between 1.60E þ 2 and 5.67 E þ 12/min. The decomposition kinetic mechanism of melina is concluded to be a multi-step reaction