Phase composition of bauxite-based refractory castables

Sintering and characterization of flyash-based mullite with MgO addition

“…On the one hand, fresh pores were formed because of the generation of gases such as CO 2 (from MgCO 3 ) and H 2 O (from crystallization water and Mg(OH) 2 ) via the decomposition of ((MgCO 3 ) 4 ·Mg(OH) 2 ·5H 2 O) below 400 • C. 20 Also, during further firing, the dehydroxylation of diaspore (AlO(OH)) and kaolinite (Al 2 O 3 ·2SiO 2 ·2H 2 O) in bauxite and the consequent combustion of residual carbon in flyash resulted in the production of new pores. 11,20,21 On the other hand, during viscous flow sintering at high temperature, due to the addition of magnesia, much more multiple oxide liquid phase was generated, resulting in the retardation of the pore elimination process. Therefore, large pores were formed, though the thickness difference of the measured samples has a slight effect on pore size according to the Hagen-Posieuille equation during the bubble-point test.…”

Lattice strain estimation for CoAl2O4 nano particles using Williamson-Hall analysis

“…On the other hand, Hasin et al [20] decided not only the metal oxides but, also metal chlorides, nitrates and acetate salts, can be used as starting material to synthesis NiAl 2 O 4 spinel by metal complex method. Other reaserch works prepared spinel nano powders via sol-gel and coprecipitation technique [21][22][23].…”

Optimized microstructure with nano‐alumina and its effects on properties of corundum spinel castables

“…Further applications of nano‐powders in refractory castables were reported in the literature . Rapid diffusion paths and very high surface energy usually make them relatively reactive in the refractories, which frequently encounter the aggressive environments, particularly in the cement and steel industries . According to previous reports, some properties such as corrosion, hydration, thermal shock resistance, and strength of refractory castable are improved by addition nanoparticles such as ZrO 2 and TiO 2 .…”