Fused Cast Bricks

Fused Cast Bricks are mostly used for glass industry.Typical applications are superstructures, skew blocks, wall bricks and upper-checker in regenerators, paving, sub-paving and forehearth blocks in float glass furnaces...

Fused Cast Bricks are mostly used for glass industry.Typical applications are superstructures, skew blocks, wall bricks and upper-checker in regenerators, paving, sub-paving and forehearth blocks in float glass furnaces.

AZS fused cast block is also called fused cast block which is abbreviated as AZS because it contains Al2O3-ZrO2-SiO2. Fused cast AZS block is made from pure alumina powder and Zircon sand (composed of 65% zirconia and 34% SiO2). After Alumina powder and zircon sand melting in electric furnace, they are cast into various molds and cool themselves down to become white solid. Because of the different content of Zirconia from 33%-41%, our fused cast AZS blocks can be divided into three types AZS—33#,AZS—36# and AZS—41#.

The term Fused Cast refers to a manufacturing process in which the ceramic bonding is obtained by the solidification of a mixture which has been melted in an electric furnace and cast in liquid state into molds.

How it can be good quality fused cast bricks ?

  • Oxidation level of the melted liquid: The oxidation level strongly influences compactness, blistering tendency, exudation, stoning and corrosion resistance. The optimal oxidation level depends on the melting process and proper control of the melting parameters within the furnace.
  • Compactness, cohesion and homogeneity of the crystallographic structure: The level of oxidation-reduction in the cast liquid and the solidification conditions strongly influence the quality of the crystaline structure and the compactness of fused cast products. These determine product behavior during utilization.
  • Size and position of the shrinkage cavities: In order to provide the best possible quality in terms of product end-use, the material contraction which occur during the solidification process must be carefully controlled, as it affects the homogeneity of the piece, the volume and location of the shrinkage cavity, and the residual stress.

Fused cast bricks casting types :

General casting PT: Due to volume shrinkage from liquid-solid transform and rapid solidification of a casting ,normal cast blocks have their cavity located under the filling scar. The feasible limits of cavity can be evaluated and indicated by the volume-weight testing of blocks in-situ according to the technical specifications.

Tilt casting QX:  In this method, the casting cavity is located towards the lower back face of a block; the feasible limits of cavity can be evaluated and indicated by the volume-weight testing of blocks in-situ according to the technical specifications. Meanwhile, blocks which height less than 900mm are not suitable to be manufactured by this process.

Reinforced casting ZWS; In this developed process, reduced cavity is located towards the bottom of a casting; a little part of the cavity will be remained at the end of the block after the header cutting. Block evaluation in-situ begins from the determination for the feasible size and deepness of cavity remainder at first and then to the volume-weight testing of blocks according to the technical specifications.

Void-free casting WS:  In the process, additional liquid from the header fills sufficiently into a casting; the header is then cut off leaving a block free of casting cavities. Block evaluation in-situ includes the acceptance or rejection for somewhat trace of cavity remainder which perhaps appeared and the volume-weight testing of blocks according to technical specifications.
NR-33 is the Alumina-Zirconia-Silica fused cast material with >32% ZrO2 made by oxidizing process. Its microstructure makes a feature of zirconia , corundum and eutectoid crystals assembly, certain amount of the glassy matrix, resulting in unique properties. The good cast-ability of this material enables the products of many complex and varied shapes.

 

Fused Cast Blocks