https://hdl.handle.net/11256/808 2026-04-22T13:26:43Z 2026-04-22T13:26:43Z Mohan, Soumya Pilchak, Adam L. Kalidindi, Surya R. https://hdl.handle.net/11256/995 2021-08-09T04:39:56Z

Use of spherical nanoindentation protocols to study the anisotropic mechanical response of alpha-beta single colonies in Ti-6Al-4V alloy Mohan, Soumya; Pilchak, Adam L.; Kalidindi, Surya R. The recently developed spherical nanoindentation stress-strain protocols were employed in this study to investigate systematically the anisotropic elastic and yield response of the α-β single colonies in a Ti-6Al-4V alloy. This was accomplished by indenting colonies with different lattice orientations of the α (measured by electron back-scattered diffraction) in the polycrystalline sample. It is seen that the employed protocols are capable of providing reliable and consistent information on the anisotropy of the colonies in a high-throughput manner, compared to the other approaches being explored in current literature. Furthermore, the responses measured in this study have been compared against similar measurements on differently oriented grains of primary α. It was noted that the α-β colonies exhibit distinctly different elastic and plastic anisotropy compared to the primary α grains. A dip in the indentation yield properties at 45 degrees declination angle is observed, and a lack of anisotropy is observed in the elastic properties.

Millan Espitia, Natalia Mohan, Soumya Pilchak, Adam L. Kalidindi, Surya R. https://hdl.handle.net/11256/989 2020-08-28T01:30:21Z

Spherical nanoindentation stress-strain curves of primary-α grains in Ti5-2.5, Ti811, Ti64, Ti6242 and Ti6246 alloys Millan Espitia, Natalia; Mohan, Soumya; Pilchak, Adam L.; Kalidindi, Surya R. Recently established spherical indentation stress-strain protocols have demonstrated the feasibility of measuring reliably the mechanical responses at different material structure length scales in a broad range of structural alloys. In the present study, we apply these high-throughput protocols on the primary α-phase grains in polycrystalline samples of Ti-5Al-2.5Sn, Ti-8Al-1Mo-1V, Ti-6Al-4V, Ti-6Al-2Sn-4Zr-2Mo and Ti-6Al-2Sn-4Zr-6Mo to aggregate a large experimental dataset that documents systematically the effects of α -phase chemical composition and grain orientation on the measured values of indentation modulus and the indentation yield strength. This dataset is being offered to the materials community in an open repository to allow further analyses of the effect of chemical composition of the α -phase on its single crystal elastic and plastic properties. This study clearly establishes the feasibility and tremendous value of spherical indentation stress-strain protocols for documenting the grain-scale anisotropic mechanical responses of different α -phase compositions in high-throughput assays.

Weaver, Jordan S. Priddy, Matthew W. McDowell, David L. Kalidindi, Surya R. https://hdl.handle.net/11256/809 2016-08-31T01:55:13Z

Spherical nanoindentation stress-strain curves of commercially pure titanium and Ti-6Al-4V Weaver, Jordan S.; Priddy, Matthew W.; McDowell, David L.; Kalidindi, Surya R. Spherical nanoindentation combined with electron back-scattered diffraction was employed to characterize the grain-scale elastic and plastic anisotropy of single crystal alpha-Ti for commercially pure (CP-Ti) and alloyed (Ti-64) titanium. In addition, alpha-beta Ti (single colony) grains were characterized. The data set includes the nanoindentation force, displacement, and contact stiffness, the nanoindentation stress-strain analysis, and the alpha-Ti crystal orientations. Details of the samples and experimental protocols can be found in Weaver et al. (2016) Acta Materialia doi:10.1016/j.actamat.2016.06.053.