Using alumina-rich MgAl2O4 spinel AR78 and 97 fused magnesite as raw materials, brine as the binder, magnesia alumina spinel bricks close to theoretical composition and spinel bricks with zirconia have been prepared. Then the influences of zirconia on the properties of MgAl2O4 spinel bricks are researched. The results show that: (1) After the addition of zirconia, the direct bonding structure formed between spinel and zirconia can strengthen matrix structure and promote sintering, so the structural properties, the alkali resistance performance and the creep property of MgAl2O4 spinel bricks are all improved. (2) The optimal addition of zirconia is 6%, with which the spinel bricks have well alkali resistance performance and creep property of which the final creep rate is -1.46% after creep experiment for 50h.

The theoretical composition was made from MgO-rich MgAl2O4 (MR66) and alumina powder. The static crucible method was used to study alkali-resistance of the block samples. It has been observed that alkali steam permeated into the hole and reacted with corundum particles that produced β-Al2O3 by means of XRD, SEM and EDS. It led to volume expansion, cracks and melting erosion of corundum particles. The specimen of the 32% content of MgO has good physical and chemical properties and excellent alkali erosion performance. So the specimen is suitable for oxy-fuel combustion for glass melting furnace.

Unfired specimens were made with different aluninum content (0,2%,4%,6%,8%) respectively ,using high pure magnesia , magnesia-spinel and Aluninum as the main raw material. Unfired specimens were treated under the condition:110°C×24h drying,then 300°C×6h heating treatment.The properties and microstructure of the specimens were analyzed to investigate the reaction mechanism of these speciments and RH refinery slag.The result are shown that the addition of aluninum improves cold crushing strength of specimens,reaching to 63Mpa. The specimen with aluninum content of 8% shown the best slag resistance. The reaction mechanism between aluninum-magnesia-spinel complosite material and RH slag is different from magnesite-chrome brick. The major penetration element is Ca, and the Ca elment penetrated into the matrix reacts with corundum turning out a CA2 protective layer which can stop penetrating of slag.

Using alumina-rich MgAl2O4 spinel AR78 and 97 fused magnesite as raw materials, brine as the binder, magnesia alumina spinel bricks close to theoretical composition have been prepared. The phase composition and microstructure of the specimens were analyzed and characterized. The alkali resistance property of specimens was researched using static crucible method. The erosion mechanism of alkali vapor to specimens was studied by XRD, SEM and EDS. The results show that: (1) The alkali resistance property of MgAl2O4 spinel bricks were improved obviously when the addition of magnesite is more than 7%. (2) The alkali resistance property of MgAl2O4 spinel bricks is the best when the addition of magnesite is 10.3%.

The Al-Al2O3 specimens of the carbon-free sliding gate are made from sintered corundum, white fused corundum, activated alumina powder and aluminum. The Al contents of the metal Al-Al2O3 composite sliding gate are 3%, 6%, 9%, 12% and 15% respectively. The specimens are treated with three different processes (200°C drying, Nitriding and CO atmosphere). The results show that, the specimen of Nitriding has the best performance. Especially, the specimen, whose Al content is 9% and is treated with Nitriding, has relative lower apparent porosity, higher cold crushing strength and hot modulus of rupture, which makes it posses the superior combination property.