摘要 |
A ceramic filament comprising a tungsten core and an outer layer of silicon carbide, the tungsten core and the outer layer being separated by an intermediate layer of titanium carbide. Also claimed is a process for the deposition of a titanium carbide coating on a tungsten filament which comprises heating the filament and passing the heated filament through a deposition chamber containing gases which on contact with the hot filament deposit the coating, the gases comprising a hydrocarbon and a titanium halogenated compound, said titanium halogenated compound contacting the tungsten filament before the hydrocarbon. <IMAGE> |