New building materials market has been very hot, refractory raw materials will be of high purity mainly natural selection and synthetic.
1, three stone materials
Development and utilization of the raw material of the three stone, andalusite, sillimanite, kyanite raw materials, can improve the microscopic structure and thermodynamic properties of the Al-Si refractory. Three stone in the high-temperature phase to mullite, mullite expansion coefficient is small, help to improve the thermal shock resistance of the material. Andalusite phase diffusion thermal stress is formed numerous tiny voids added in the material so that the stress within the refractory material to be released, thereby improving the thermal shock resistance. The sillimanite is fully mullitization the temperature is higher, will help improve high temperature creep resistance. In addition, the effect of volume expansion due to mullitization accompanied the high temperature creep favorable.
2, high-quality synthetic refractory raw materials development
Natural raw material usage of the developed countries in reducing the high-purity synthetic material usage is increasing, the reason is the extensive use of synthetic raw materials unshaped refractories increase in the proportion of, and the extensive use of natural raw materials, clay bricks, high alumina bricks, zirconium, British stone brick production reduced. In addition, due to the extended refractory life have higher requirements, should be a large number of high-purity synthetic materials to meet such requirements.
Refractory cameras of various synthetic materials as follows:
(1) mullite-based clinker
Kaolin and industrial alumina as raw material by wet grinding, vacuum extrusion, and then calcined at high temperatures from refining. Has good thermal mechanical properties, has good application prospects in kiln furniture and monolithic refractories.
2 cordierite clinker
With kaolin and magnesia as raw material by wet grinding, vacuum extrusion molding, and high-temperature calcination.
(3) Calcium magnesium clinker
The development of clean steel, low carbon steel, high-oxygen steel and stainless steel, making the basic refractories containing free calcium oxide was receiving attention.
(4) eutectic composite fused material
Bauxite-based fused alumina, bauxite-based fused mullite stone, bauxite-based fused mullite - zirconia, fused alumina - zirconia, fused magnesia - zirconia and other synthetic materials has also been rapid development.
(5) dense spherical hollow synthetic mullite aggregate
The hollow shell wall thickness of 0.2-5mm, diameter 1.5-40mm, the surface can be smooth, can also be uneven, the spherical shell can be a single layer, and can also double. The surface of the projecting portion can be dense, but also may be hollow. For castable, not only can improve the thermal insulation properties of the material, to reduce the bulk density, without destroying its strength.
The refractories will receive a wide range of needs of the market, the market space.
