Effect of different bonding agents on sintering behaviour of al2o3-sio2 based mortar

Abstract

Refractory Mortar is a mixture of fine particles which are used in the form of a paste to bind refractory bricks after the addition of water to the mixture.The composition and chemistry of the mortar need to be similar to that of the brick to be joined by the mortar.The service life of a refractory lining not only depends on the properties bricks but also on joints made by mortar.More precisely to say mortar joints in a refractory walls is the weakest part of the wall.Mortars used to bind the bricks are generally low cost materials as compared to bricks.But its importance is much more than brick.Because it forms the lining between the refractory bricks;if failure occurs,it causes the damage of the whole refractory lining.In the present study,attempts have been made to develop 45% Al2O3 mortar to join 45-50% alumina bricks with suitable binder.Chinese bauxite,fire clay grog, and sillimanite sand have been used as aggregates to prepare the mortar. Three binders chosen are bentonite, plastic clay and sodium silicate liquid. Attempt has been made to study the effect of binders on the physical and mechanical properties of the mortar thus developed. Analysis has been done by considering all the physical and mechanical properties of the mortar found by using different binders in different percentage. It has been found by using bentonite as a binder that, all the mechanical properties of the mortar increases with increase in bentonite content also with increase in temperature. It is also concluded that by using plastic clay as a binding agent, mechanical also physical behaviour of mortar increases with increase in plastic clay content. By using sodium silicate liquid as a binder all the mechanical properties of the mortar specially bond strength of mortar increases drastically with increase in temperature also with sodium silicate liquid content as compared to other binders studied. Among all binder studied, sodium silicate liquid was found to be better than other.