Two powders were used: one with an average particle size of 40
m; the other, 5 m. Both powders contained 5 vol% TiC. Two
different viscosity binders were tried: low, 60 cP; high, 3500–5600
cP. The finer (5-m) Ti3SiC2 powder formed a viscous thixiotropic slurry, which gave good flexible tapes, and thus additional
experiments were conducted only with the 5-m powders and the
high-viscosity slurry. A doctor blade was used for the tape casting;
the gap thickness was fixed around 400 m. The tape was cast and
allowed to dry overnight; the thicknesses of the tapes after drying
were 100 m. The tape was cut into smaller pieces of 1.5 3
cm2, stacked (40–50 tapes, roughly 10 mm), and warm-pressed for
10 min at 200°C at 2.5 or 6 MPa. To burn out the binder, the tapes
were heated at the rate of 5°C/min to 500°C for 3 h in Ar, before
being heated directly to 1600°C at a rate of 8°C/min. The samples
were held at temperature for 4 h. The resulting sample surface was
shiny, and large grains were visible to the naked eye.