1991 Volume 38 Issue 3 Pages 374-377
Several mechanical properties and the microstructure of the machinable silicon carbide, which is fabricated by sintering β-phase silicon carbide fine powder mixed with polysilastyrene in argon atmosphere, has been evaluated. The bending strength reached 230 MPa at room temperature and there was no degradation in strength up to 1500°C. Such good strength seems to be originated from the tight interconnection among silicon carbide particles formed even at low sintering temperature with the aid of the polysilastyrene forming β-phase silicon carbide. TEM obsevation and X-ray analysis revealed the presence of turbostratic structure ribbon of carbon in nano-scale formed in the pores. The ribbon-like carbon is also one of the productds of polysilastyrene. The machinability of this material is considered to be provided by the presence of carbon, which helps the lubrication in machining, in addition to the porous structure. This material is expected to be high-temperature structural compornents.
