Determination of the single-phase constitutive relations of α/β dual phase TC6 titanium alloy

作者：Shi, Ran; Li, Guoju; Nie, Zhihua; Fan, Qunbo^*

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2016, 675: 138-146.

DOI：10.1016/j.msea.2016.08.057

• Synchrotron x-ray diffraction
• EBSD
• Titanium alloys
• Constitutive relation
• Schmid Factor

The constitutive relations of alpha and beta phases in a TC6 titanium alloy were determined by implementing a two-phase elastic-plastic self-consistent (EPSC) framework combined with the evolution of lattice strains; these strains were obtained via in-situ tensile loading synchrotron-based x-ray diffraction experiments. It was found that the {200}(beta) reflection has the lowest stiffness and load partitions prior to the alpha phase during the elastic loading stage in this alloy. The simulated parameters including the diffraction elastic constant and initial yield stress of lattice reflections exhibited satisfactory correspondence with the experimental results. Further analysis of the characteristics of the Schmid Factor (SF) distributions of the main slip systems revealed that the elastic-plastic transition process in the alpha phase occurs over a prolonged period. In contrast, the beta phase undergoes a transient process owing to its relatively more concentrated SF frequency distributions, than those of the alpha phase. In addition, the fitted stress-strain curve of each phase was compared with the measured macro stress-strain curve obtained from the in situ experiment. It revealed Young's moduli of 110.3 GPa and 104.5 GPa, and yield stresses of 877.8 MPa and 969 MPa, for the alpha and beta phases, respectively.

• 出版日期2016-10-15
• 单位北京理工大学