The aim of the work is the development of aluminium titanate containing low silica kiln furniture for the sintering of powder metals. In the past a lot of different materials were used, in the meantime based on cordierite containing ceramics due to the need of a high thermal shock resistance. The second phase of this kind of material was more or less mullite, which can not decrease the amount of silica in the product really. This kind of ceramic has meanwhile two disadvantages. The first one is the silica content which causes contact reactions with the metal powder parts in the sintering process with the result of surface defects on the sintered parts, especially a decrease in the hardness of the surface. The second disadvantage is the lower ability of positive reactions such as absorption of temporary binders through the sintering process, especially in the case of sintering parts which are produced by the MIM process. The reason for that was found in the porosity itself and the pore size distribution. The newly developed kiln furniture based on corundum with a silica content of less than 5 % and additionally doped with aluminium titanate has decreased the contact reaction down to zero. Due to the special composition the above mentioned positive reactions through the sinter process are also possible. And with the combination of corundum and aluminium titanate resulting in an enhanced thermal shock resistance the new kiln furniture can be used in all kinds of fast firing processes.
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