TITLE:
The Effect of Nano-Alumina Particles Generated in Situ in the Matrix of Ultralow and No Cement 85 wt% Al2O3 Refractory Castables
AUTHORS:
José Antonio Alves Júnior, João Baptista Baldo
KEYWORDS:
Low Cement Refractory Castable, Alumina Nanoparticles, Elastic Modulus, Impulse Excitation Technique
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.7 No.6,
June
27,
2019
ABSTRACT: Advanced high alumina refractory castables of ultra-low and to cement types, are well-known because of their ability on developing similar and/or superior thermal and mechanical properties. Following the recent trend of including nanoparticles in refractory castables, in this work, it is presented a novel way to obtain the benefit effects on the thermal and mechanical properties, promoted by the development in situ, of alumina’s nanoparticles in the matrix of castable (85 wt% Al2O3). The alumina nanoparticles were originated in situ after firing, due to the pyrolysis and oxidation of an aqueous resin, produced by the Pechini process. The resin played a double role, one as mixing liquid vehicle and the other as the aluminum oxide nanoparticles precursor. The results indicate a strong increase in flexural strength and elastic modulus as well as leading to a higher residual strength after thermal shock.