Growth of (αTi) grain-boundary layers in Ti–Co alloys

Abstract

The influence of temperature on the formation of the (αTi) grain-boundary interlayer in alloys Ti–2 wt % Co and Ti–4 wt % Co in the two-phase region (αTi) + (βTi) of the Ti–Co phase diagram is studied in a temperature range of 690–810°C. The growth kinetics of the thickness (Δ) of the grain-boundary interlayer of the (αTi) phase in the Ti–2 wt % Co alloy is investigated at 750°C. Δ depends on the annealing time as ~ t 1/3. The analysis of the results of experimental observations makes it possible to assume that an increase in Δ is the manifestation of coalescence of (αTi), which is controlled by the bulk diffusion.