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Pressure-free sintered silicon carbide ceramics is made of high-purity and ultra-fine silicon carbide powder with a small amount of sintering auxiliaries, such as boron and carbon, sintered under high temperature of 1950~2100℃ in atmospheric inert gas or vacuum atmosphere, and the resulting products are almost completely compact ceramic materials with excellent mechanical properties.
Diversity of non-pressure sintered silicon carbide ceramic products:
In recent years, with the development of sintering of silicon carbide products, non-pressure sintering process is adopted for silicon carbide ceramics, and the properties of sintered products are excellent, so it has become a promising sintering method.
Through non-pressure sintering, the forming pressure of silicon carbide ceramics is 140MPa and the holding time is 90s; The binder content is 3% of the total material quality; Silicon carbide ceramic sintering with elements C and B4C as sintering auxiliaries belongs to solid phase sintering. The sintering process is mainly controlled by the diffusion mechanism, and the sintering temperature is 2150℃. Silicon carbide ceramic sintering with metal oxides such as Al_2O_3, K_2O, Na_2O and MgO as sintering AIDS belongs to liquid phase sintering, the sintering process is mainly controlled by interface reaction, and the sintering temperature is 1350℃.
In addition, the silicon carbide ceramics obtained by non-pressure sintering process have a density of 3.16g/cm-3(relative density 98.75%) and a compressive strength of 550MPa. Add the appropriate contain