The evolution of the microstructure
of the SiC-containing composition is very similar to that of
the STD composition until 1180 ◦C (figures of the STD composition
not reported here for the sake of brevity), and is
characterised by a porous texture made up of a network of
highly interconnected, small pores at lowtemperature (1140 ◦C).
When the temperature rises (1180 ◦C), the liquid-phase content
increases and the liquid-phase viscosity decreases.