Pressureless Sintered Silicon Carbide Sealing Ring
Silicon carbide ceramic seal rings have a higher friction coefficient than alumina ceramics and hard alloys. Therefore, they are used for high PV values, especially when working with strong acids and alkalis.
First, the ingredients are made, the slurry is proportioned, and the initially mixed slurry is granulated by a watering can.
In the second step, press molding, the prepared powder is placed in a prelubricated metal grinding tool and then is put on a press, and the pressure is maintained at 45S with a pressure of 16T and the mold is then released.
The third step, before the sintering preform, sintering: sintered in a vacuum furnace at 2100 °C -2200 °C 8h sintering, remove and place at room temperature.
Silicon carbide ceramic seals are pressureless sintered. The relative density of sintered products can reach over 96%, and the products do not undergo excessive plastic deformation before and after firing.
The fourth step: grinding drilling and milling, due to the high hardness of silicon carbide ceramics, the final cracking or cracking occurs in the grinding process, so choose artificial diamond grinding wheel.
Finally, grinding the sealing surface is completed by two steps of rough grinding and static grinding.