The influence of trace boron addition on grain growth kinetics of the beta phase in the beta titanium alloy Ti-15Mo-2.6Nb-3Al-0.2Si

摘要

Trace boron additions to the beta titanium alloy Ti-15Mo-2.6Nb-3Al-0.2Si (wt. percent) lead to significant grain refinement of the as-cast microstructure and precipitation of TiB whiskers along the grain boundaries. The TiB is very effective in restricting the beta grain boundary mobility by Zener pinning. A model is developed to predict the maximum grain size as a function of TiB size, orientation and volume fraction. Good agreement between model predictions and experimental results was obtained.