Dynamic Recrystallization in Titanium Alloys: A Comprehensive Review

Abstract This article is an attempt at highlighting recent advances made for understanding and modeling the phenomenon of dynamic recrystallization (DRX) prevalent in titanium alloys. Research work in recent years has focused on providing a rigorous description of key factors that influence the DRX process such as the effect of grain size, stacking fault energy, and other microstructural descriptors, thermomechanical processing, etc. The key addition of this work to existing literature is a critical commentary of important experimental as well as modeling efforts in recent years related to observing DRX in hexagonal close-packed (hcp) metals. We have attempted to directly compare, with reference to experiments, the effects of process variables such as strain rate, temperature, and composition on the occurrence of DRX in titanium alloys. A comprehensive review has been made of the experiments that have been carried out specifically to observe DRX in titanium alloys. This can aid modeling and validation efforts to accurately capture different facets of DRX for titanium alloys and other hcp metals. A similar comparison of the drawbacks and insights obtained from applying various modeling strategies, viz., FEM-based, phenomenological, or grid-based numerical methods for various alloys can provide valuable insights to choose appropriate modeling schemes or develop novel techniques to predict aspects of DRX such as preferred nucleation sites and evolution of microstructure, including grain boundaries and primary and secondary phases.