Diamond fibres were produced in a hot filament reactor by chemical vap
our deposition of a 40 mu m thick layer of diamond on to titanium-coat
ed iron and iron-chromium wires. In the 40 h deposition time carbon di
ffused through the titanium and steel and produced carbide microstruct
ures with hardness values of similar to 3234 and 5390 N mm(-2) for the
Fe and Fe-Cr cores, respectively. During cooling thermal stress fract
ure of the diamond was avoided by stress relief cracks in the disorder
ed graphite layer at the diamond/Ti-rich layer interface.