Dispersion properties of alumina powders in silica sol

Halos mechanism in stabilizing of colloidal suspensions: Nanoparticle weight fraction and pH effects

“…1 The homogenization, dispersion and stabilization of ceramic particles in liquids are of primary importance for the preparation of highly performance ceramics through colloidal processing. 2 By tailoring interactions between colloidal particles, one can design stable suspensions. Attractive van der Waals forces must be balanced by repulsive interactions to engineer the desired degree of colloidal stability.…”

“…3,[17][18][19][20] In "nanoparticle halos" mechanism, in addition to regulate the interparticle interactions, the inorganic nanoparticle hydrosol is considered as an efficient dispersant agent for ceramic powders, because it can not only provide high binding strength for ceramic bodies due to its conversion to a solid gel at relatively low temperature, but also improve the sinterability of ceramic powders. 2,21,22 But few studies have been conducted on the stabilization mechanism of this method. Also, the effect of different key variables such as the nanoparticles volume fraction and pH has been investigated in only a few especial bidispersed systems.…”

Rheological performance of high alumina nano-bonded refractory castables containing carboxylic acids as additives

“…In all cases, the pH and conductivity values of alumina-colloidal silica systems were higher than the plain silica sols. As reported by the literature [9,13], the increase in pH due to the addition of alumina in water is caused by an ion exchange reaction between sodium on the surface of alumina and hydrogen ions in the aqueous solution. According to Kelso and Ferrazzoli [14], the surface chemistry of alumina, especially its sodium content, considerably affects the stability of aqueous suspensions containing this oxide.…”

“…Most publications presented in the literature are focused on discussing the impact of setting agent additives [6,7], whereas some efforts have also been reported related to the incorporation of appropriate dispersants to alumina-colloidal silica systems [8,9].…”

Effect of a Magnetic Field on the Flow Assisted Corrosion of Low Alloy Steel in an Alkaline Solution

“…4,5) Since both the alumina particles and magnetite oxide or its particulate contain the negative zeta potential at pH 10.4 solution, there is no deposition of alumina particles on the test oxide surface. 6,7) The test material was SA106 Gr.C steel, the main steam piping in a pressurized water reactor (PWR). It showed similar chemical compositions and mechanical aspects to the CANDU feeder pipe material SA106 Gr.B steel.…”