Microsilica-Gel Bonded Refractory Castables with Improved Set-Behaviour and Mechanical Properties

Hong Peng1, Bjørn Myhre2

1 Elkem Silicon Materials, Kristiansand/Norway
2 Elkem Silicon Materials, Kristiansand/Norway


Volume 7, Issue 3, Pages 69 -79


Silica-sol bonded no-cement refractory castables are attractive to the industry due to their high temperature performance and fast dry-out in comparison to low cement castables. However, these castables are not widely used, due to inadequate green strength and long settime/complex set-behaviour. In this paper, dry silica-gel bonded nocement castables were developed using microsilica-gel as binder and the novel SioxX-Zero as a speciality additive package. SioxX-Zero has been purposely developed for use in microsilica-gel bonded nocement castable systems and the main functions are to control flow properties and set characteristics. When SioxX-Zero replaces other dispersants, the set behaviour and green mechanical strength of the NCCs are substantially improved. Furthermore, the performance of various high alumina aggregates was evaluated and the results confirm that in comparison with silica-sol, the microsilica-gel bonded refractory NCCs exhibit improved set-behaviour and green strength.


no-cement castable, silica-sol, microsilica, gel-bond, additive


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