Reaction-sintered silicon carbide is a new type of high-tech ceramics, which has high strength, high hardness, good wear resistance and corrosion resistance, and is widely used in metallurgy, petrochemical, electronics, aerospace and other fields. The product with silicon carbide abrasive auxiliary carbon black, graphite and various additives, using dry pressing, extrusion or pouring methods to make porous quality, then the following together to understand the production method of reactive sintering silicon carbide!
Reactive sintering silicon carbide The invention is a relatively mature technical scheme after thousands of tests by the inventor for many years to promote the raw material formula and production process, especially the unique continuous sintering process.
In claim 1 of the invention, the weight fraction of silicon carbide powder is 5~8 parts, carbon black is 0.5-1.5 parts, graphite is 1-1.5 parts, and binder is 0.1-0.5 parts. Among them, the grain size gradient of silicon carbide is sic(90-30m)3-5 parts, sic) 30-0.8m)2-3 parts. The methyl cellulose and PVA powder of gazelle were put into the appropriate amount of water 0.1-0.5 parts respectively, and the transparent solution was obtained after heating.
1. Mix all kinds of powders, adhesives and solutions prepared according to the formula and stir well.
2, clean the casting mold vacuum, reach 0.1Mpa, pressure injection of the mixed slurry. After a certain time, the slurry is released and the blank is taken out. Keep at 30-70 for 18-20 hours for drying.
3. Trim the billet according to the requirements of the drawing.
4, put the reaction sintering billet into the furnace, add the weight of 1-3 parts of metal silicon, vacuum sintering. The process is divided into low temperature 0-700, maintained for 3-5 hours; Medium temperature 700-1400, keep for 4-6 hours; Keep at high temperature 1400-2200 for 5-7 hours. Drop the temperature below 150 stop the furnace and open the furnace.
5, sand blasting treatment grinding product surface silicon slag, with sand blasting grinding.
6, oxidation treatment products into the oxidation furnace, 24 hours to 1350, natural cooling. Take out, check and put into storage.
The raw materials and proportion adopted by the method of the invention are scientific and reasonable, so that the blank has sufficient voidage and the blank has better density; Better sintering heating rate, temperature and holding time ensure the high bending strength of the product. The main performance and quality of this method have reached the international advanced level. Its main indicators are as follows
Reaction sintering silicon carbide specific implementation
Embodiment 1 Method for manufacturing reaction-sintered silicon carbide bundles:
1, the raw material to take the adhesive weight of 0.3 parts, add a certain amount of water evenly stir, weight of 6.8 parts of silicon carbide powder (particle size of 90-30m of 3.8 parts, 30-0.8m of 3 parts), carbon black 1 part, black
2. When pouring, first clean the mold used, align the mold, fix it with fasteners, draw the slurry out of the tank with pressure, fill the tank with 0.1Mpa pressure nitrogen, perform pressure pouring, and push the slurry into the mold. After reaching 1 hour, the slurry is released, and after 6 hours, the mold is removed, the blank material is taken out, and the drying room is dried. 30-70, 18-20 hours to remove. 3. When repairing the blank, first check whether the blank meets the design requirements. When meeting the requirements, repair the blank according to the drawing. After inspection, send to high temperature drying room.
4. After the moisture of the reaction sintering billet reaches 1%, take it out, clean the billet with blowing air and weigh it. Add 2.9 parts silicon metal. Nitrogen can be pumped into the vacuum sintering. Sintering process at 700 low temperature for 4 hours; Medium temperature 1400, 5 hours; High temperature 2200,6 hours. When the temperature drops 12 hours and reaches 150, stop the operation in the furnace and open the furnace.
5. After the sandblasting treatment product comes out, the silicon standard Chartered on its surface is ground and grinded with sandblasting.
6. The purpose of oxidation treatment products is to remove the oxides generated during the sintering process. The product is heated to 1350 for 24 hours in the oxidation furnace and then cooled naturally. After removal, it is put into storage through inspection.
The raw materials and proportion adopted by the method of the invention are scientific and reasonable, so that the blank has sufficient voidage and the blank has better density; Better sintering heating rate, temperature and holding time ensure the high bending strength of the product. The main performance and quality of the products produced by this method have reached the international advanced level.
The above is the production method of reactive sintering silicon carbide, if you need more information, please feel free to contact us!
Post time: Jun-13-2023