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Powder metallurgy (PM) Ti-22Al-24Nb-0.5Mo (at.%) alloys were prepared by hot isostatic pressing. In order to study the feasibility of PM ? ring rolling combined process for preparing Ti 2 AlNb rings, thermal mechanical simulation tests of PM Ti 2 AlNb alloys were conducted and two rectangular PM rings (150 mm in height, 75 mm in thickness, 350 mm in external diameter) were rolled as a validation experiment. Experimental results show that the flow stress of Ti 2 AlNb alloys exhibited a significant drop at the very beginning of the deformation (true strain \0.1), and became stable with the increase in strain. Stress instability phenomenon of PM Ti 2 AlNb alloys was more obvious than that of wrought alloy. Flow stress fluctuation at the initial stage of deformation is related to phase transition of Ti 2 AlNb alloys which strongly depends on heat treatment and thermal mechanical deformation process. Processing windows during initial stage of ring rolling process is very crucial. A sound PM Ti 2 AlNb rectangular ring blank (height = 150 mm, thickness = 30 mm, external diameter = 750 mm) was successfully rolled in two passes by using the improved heat preservation method and optimized rolling parameters. Tensile properties of PM Ti 2 AlNb alloy were improved, and the porosity was reduced after ring rolling.

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