Views: 316 Author: Joanne Qiao Publish Time: 2018-03-26 Origin: Google
The preparation of high‐purity mullite powders (3Al2O3· 2SiO2) was examined using aluminum salts or boehmite and fumed silica. The combination of aluminum sulfate and fumed silica was found to have the highest quality for mullite powder. A slurry consisting of an aqueous solution of aluminum sulfate and fumed silica was dried and heated at 1350°C and was attrition‐milled for 2 h. The mullite powder obtained was composed of submicrometer, uniform, and equiaxial particles with narrow size distribution. It was hot‐pressed at 1600°C for 1 h under 10 MPa or was sintered at 1650°C for 3 h. The bulk densities of the products made by both processes were 3.16 and 3.09 g/cm3.
Characteristics:
1. High refractoriness.
2. Aluminum content high, the iron content low.
3. High volume density.
4. Thermal expansion coefficients of small.5. Physicochemical stability.
6. Fully calcined
7. Dust content low
8. The specification standards.
Advantages:
1. Easy out of shell.
2. No deformation.
3. No reduced scale.
4. Good brightness , Good finish .
5. Product rate is high.
Applications:
1) Product is suitable for Stainless steel, alloy steel, carbon steel, heat-resistant steel, titanium alloy, nickel alloy, aluminum alloy, cast iron, cast copper complex precision castings and big, medium and small castings, etc.
2) Product is suitable for precision casting ,Silicon Sol investment casting, lost wax casting ,Cast steel, cast copper, Vacuum casting, plaster filler v-process, casting coatings, casting mold shell, etc.