| The formation of titanium diboride (Ti82) whiskers through
carbothermal reduction of Ti02 and 820 3 was studied in the temperature
range of 900°C to 1600°C at one atmospheric pressure
of argon and one atmospheric pressure of nitrogen. K2C03 and
NiCI2 were used to aid the whisker formation. Ti02, NiCI2, K2C03,
carbon black and 8 20 3 were taken in a definite proportion. TiN
was formed as a major phase in nitrogen, whereas Ti82 was the
major phase in argon. Small quantities of TiC were also formed
in argon. Whiskers of Ti82 were observed at 940° C-1200°C. Above
1400°C, the formation of particulates was the dominant process.
A vapour-liquid-solid growth mechanism was identified for Ti82
whisker formation. |
