Density of the samples was determined by the
Archimedes method (ASTM C373). Polished and
plasma etched (70%CF4–30%O2) sintered SiC samples
were observed using scanning electron microscopy
(SEM; LEO 438-VP). X-ray diffraction (XRD) analysis
was used to determine the qualitative composition in
terms of crystalline phases of the sintered samples.
X-ray patterns were collected with a Philips powder
diffractometer with a Bragg–Brentano geometry and
equipped with a copper anode operated at 40 kV and
30 mA (step 0.02°, time 6 s). The phase analysis was
carried out with the PC X’pert High Score software
Version 2.2a (PANalytical B.V., Almelo, the
Netherlands).