Effects and Optimization of Roll Sizes in Hot Rolling of Large Rings of Titanium Alloy

Abstract In hot rolling of large rings of titanium alloy (LRTs), the ratio of roll radii R 1 / R 2 , i.e., the ratio of the radius of the driver roll R 1 to that of the idle roll R 2 , has a significant effect on the geometric shape of the deformation zone (GSDZ) which plays a decisive role in achieving LRTs with high quality. In the study, an analytical description of the GSDZ is presented, and quantitative relationships between the GSDZ and R 1 / R 2 are determined. Then a validated coupled thermo-mechanical 3D-FE model of the process is developed in the dynamic explicit code ABAQUS/Explicit. Finally, an investigation is conducted regarding the effects of R 1 / R 2 on the quality of LRTs from the view point of GSDZ using FE simulation. The results show that there is an optimized range of R 1 / R 2 for obtaining LRTs with better end-plane quality and more uniform strain and temperature distributions.