Effect of CaO Addition on the Sintering Behavior and Microstructure of Stoichiometric Spinel

Qasid A. Saleh¹ and Baker F. Hassen^2,

¹Department of Physics, University of AL – Nahrain / College of Sciences

²Department of Physics, University of Tikrit/College of Education for Pure Sciences

Cite this paper:
Qasid A. Saleh and Baker F. Hassen. Effect of CaO Addition on the Sintering Behavior and Microstructure of Stoichiometric Spinel. International Journal of Physics. 2017; 5(2):57-62. doi: 10.12691/ijp-5-2-5

Abstract

This paper presents a study of the most important factors influencing the sintering process spinel (MgAl₂O₄) Minutes from the oxides of aluminum (Al₂O₄) and Magnesium (MgO) percentages by weight (MgO 28wt%, Al2O3 72wt%). The traditional method called solid-state reaction (SSR), single firing stage and the impact of these factors on the physical properties, and thermal as well as the fine structure and morphology of the ceramic product. It formed Spinel models through a steel mold and shed pressure (14 Mpa) using hydraulic piston at temperatures (1200, 1400°C) and soaking time (2 h) with the study of the effect of adding oxide calcium (CaO) by weight (0,2,4,6,8 wt%) spinel on the properties and behavior as sintered the research study of the most important physical characteristics (density, porosity) and (Thermal Conductivity). The results showed that the density increased and porosity decreased with higher temperatures due to the process of sintering, as it reached the highest density at the temperature of burning 1400°C which (1.88 g/cm³), which is porosity (47.48 %). Thermal conductivity was the best value (5.071 K w/cm. °C). As well as the study of (XRD, SEM). The calcined specimens spinel were characterized by XRD, It showed the presence of developed spinel also showed that the best catalyst is CaO, and (SEM). It showed that high temperature sintering temperatures increase the regularity of the Grain Growth and cohesion in the bloc, as well as minutes from the acquisition of the spherical shape of the minutes spinel.

Keywords:
spinel (MgAl₂O₄) SSR SHS MA

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