Ligantes hidráulicos e a hidrata？？o de óxido de magnésio em concretos refratários

the presence of calcium aluminate cement and hydratable alumina can significantly modify the magnesia sinter hydration behavior in aqueous suspensions. as a consequence of these studies, the present paper investigates how these binders content could affect magnesia hydration in refractory castables using hydration-dehydration tests, ph, ave, mechanical strength and porosity measurements. besides this, because for these materials the aspects related to mechanical strength, porosity and refractoriness also must be taken into account, binder-free, magnesia-free and magnesia-and-binder-free samples were also tested as references. it was found out that the deleterious effects of magnesia hydration can be greatly minimized by the binder content.