Dynamic Globularization of α-Phase in Ti6Al4V Alloy during Hot Compression

Abstract:

Ti6Al4V samples were isothermally compressed using a Gleeble^(TM) 1500D thermo-mechanical simulator. Differential scanning calorimetry (DSC), microstructural analyses, and thermodynamic calculations were used to investigate the sequence of transformation of β into α or vice-versa and the presence of different phases in the compressed Ti6Al4V sample. Globular alpha phase was revealed in the isothermally compressed sample in addition to martensitic and lamellar α/β structures. The transition temperature range of β into α-phase was determined using the DSC thermograms and thermodynamic calculated diagrams. The fraction of α-phase globulized increased as the strain rate decreased from 0.01s^-1 to 10^-3s^-1, and the spheroidization of the α-phase is only possible in a specific range of deformation temperatures.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 584-590
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.584
• Online since: May 2014
• Authors: Kalenda Mutombo*, C. Siyasiya, W.E. Stumpf
• Keywords: Differential Scanning Calorimetry (DSC), Globularization, Phase Transformation, Thermo-Mechanical Processing

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