Abstract: The processing maps were used to identify the optimal forging parameters of Ti-24Al-17Nb-0.5Mo alloy by evaluating the flow data according to the DMM model. The actual local strain rate and strain distribution in the samples were obtained by finite element calculations. The local microstructures of the deformed samples were related to the local deformation parameters and correlated with the processing maps at 0.3, 0.4, 0.5 and 0.6 of logarithmic strain. Flow regimes predicted by DMM analysis were then correlated with the local microstructural observations. Five domains of efficient coefficient could be distinguished. Unstable regions were microstructurally related to shear band formation within the α₂+B2 phase deformation field, and to flow localization at grain boundaries of B2 phase in the near B2 phase deformation field. Stable flow regimes were shown to be associated with dynamic globularization of the plate-like α₂ in the α₂+B2 phase deformation zone, and with dynamic recrystallization of B2 in the near B2 phase deformation zone.

Key words: Processing map, Local deformation, Ti-24Al-17Nb-0.5Mo alloy, Hot deformation