Tabular & other Aggregates
Aggregates are the backbone of a refractory formulation and provide dimensional stability to the refractory products. The coarser fractions add thermal shock and corrosion resistance and the aggregate fines optimize the particle size distribution and increase the refractoriness of the product.
The consistent quality of Almatis aggregates such as Tabular alumina T60/T64, Spinel AR 90 and AR 78 is the result of a well-controlled sinter process with firing temperatures above 1800° C. The use of high temperature furnaces with state-of-the-art technology permits densification of selected raw materials without sintering aids that would negatively impact the high temperature properties of the refractories.
As a result of the sinter process, the aggregates exhibit the same mineralogical and chemical composition for all fractions. Contrary to fused products where impurities accumulate in the fines, the use of Almatis sintered aggregates in refractory formulation guarantees stable and reliable behavior.
Almatis offers various sizings of aggregates from very coarse fractions to fine-ground sizes of <45 μm and <20 μm. Crushing and milling are followed by intensive de-ironing steps that result in very low free iron within the various fractions.
Ground Median Size = 2.7µm
Ground Surface Area = 2.5 m²/g
Na2O Content = 0.30%
Dense, sintered crystalline alpha alumina with 99,5% Al2O3
High purity and chemical resistance
Energy savings are possible in each step of metals manufacture. Almatis ECO-TAB® is a lower density alumina refractory aggregate newly developed for wear linings.
Alumina-rich spinel (78% Al2O3)
Used for steel ladle shapes and monolithics
More Alumina-rich spinel (90% Al2O3)
Used in monolithics and bricks for steel applications
High-purity super lightweight aggregate,
Based on calcium hexa-aluminate CA₆; non-fibrous