Material behavior of the hexagonal alpha phase of a titanium alloy identified from nanoindentation tests

This article focuses on the numerical modeling of nanoindentation tests performed on the hexagonal α phase of Ti-5553 alloy in order to identify its mechanical behavior. The main goal consists in determining the relative strength of the slip modes in the α phase of Ti-5553. This work was performed using an elastoviscoplastic crystal plasticity-based constitutive law. The difficulties in determining the slip systems that can be activated and their corresponding critical resolved shear stresses (CRSS) are discussed. Numerical predictions are compared to experimental nanoindentation curves.