Description: The name is a contraction of "Keramicalia composite material of ceramic and stainless steel fibres." Ceramics are all brittle but many have high melting points, whereas metals are non-brittle but oxidise or melt at high temperatures. Some difficult metallurgical applications are not satisfied by either ceramic or metals, but require properties of both. Keracomp is designed to meet this need.
The fibres are compacted into a mould in the highest concentration possible, and a thin ceramic slurry is infiltrated into the matrix between the fibres. On heating, the structure develops millions of micro-cracks due to the differential expansion of steel and ceramic, but the microstructure is interlocking, making it extremely difficult to break mechanically.
Think of it as a three dimensional jigsaw puzzle: It is not a solid material but millions of tiny interlocking pieces. It can be stretched or deformed without breaking and no stress points can be formed for tearing of cracking because the structure is already in millions of tiny pieces.
Maximum service temperature: Keracomp can be used at high temperatures as long as there is a thermal gradient. The whole structure should not be surrounded by heat without any source of cooling.
The chemical analysis may be varied to suit the application, but is typically about 85% alumina ceramic and high nickel content stainless steel.
Physical properties cannot be tested by conventional ceramic and refractory procedures, nor by normal metallurgical tests. The reason for this is that the material is not a solid, but is already broken into tiny pieces. In the cold crushing strength test the cube does not break. Densities are around 3 tons per cubic metre.
Applications: Nearly all applications in which refractories and steels are both known to give poor performance. Keracomp can be attached to steel.
Installation: Pack fibres as densely as easily practical into the mould. Add +22% water to the Keracomp Slurry powder and mix well until it becomes a smooth creamy pourable fluid. Pour it over the fibres and allow it to penetrate completely.
Pilot Plant code;
Dev. no. 206 and 1011