Diffusion of Cobalt in Single Crystal α-Titanium

Abstract

Diffusion coefficients of ⁶⁰Co in single crystal α-Ti have been measured over the temperature range from 871 K to 1135 K. It has been confirmed that cobalt exhibits extremely fast diffusion about five orders of magnitude faster than the self-diffusion in α-Ti. The temperature dependence of the ⁶⁰Co diffusivities parallel and perpendicular to the c axis is expressed as
D_⁄⁄=1.9×10⁻⁶exp{−(114.1±0.9)kJ·mol⁻¹⁄RT}m²s⁻¹,
D_⊥=3.2×10⁻⁶exp{−(126.1±1.2)kJ·mol⁻¹⁄RT}m²s⁻¹.
It is suggested that some interstitial-type mechanism is operative in the Co diffusion in α-Ti.