Experimental characterization and crystal plasticity finite element modeling of heterogeneous deformation in commercial purity titanium

Published

September 1, 2011

Author(s)

Y Yang, L. Wang, C. Zambaldi, P. Eisenlohr, R. Barabash, W. Liu, Mark R. Stoudt, M. A. Crimp, T. R. Bieler

Abstract

Heterogeneous deformation, including local dislocation shear activity and lattice rotation, was analyzed in microstructure patches of polycrystalline, commercial purity titanium specimens using three different experimental methods. Crystal plasticity finite element (CPFE) simulations that incorporate a phenomenological hardening constitutive model were conducted for the same region. The measured dislocation activity, using techniques associated with atomic force microscopy (AFM), confocal microscopy, three-dimensional-X-ray diffraction (3D-XRD), and nano-indentation allows assessment and guidance for strategic improvement of the accuracy of CPFE model development. The CPFE model successfully predicted most types of active dislocation systems within grains at the correct magnitudes, but the simulation of spatial distributions of strain were not always similar to experimental observations. To improve the accuracy of CPFE results, the critical resolved shear stresses for major deformation systems in α-titanium were assessed using an optimization strategy with CPFE predictions of the measured pile-up topography surrounding axisymmetric nano-indentation, which only provided modest improvements. A major challenge for model development is to effectively predict conditions where slip transfer occurs, and where geometrically necessary dislocations (GND) accumulate.

Citation

JOM Journal of the Minerals Metals and Materials Society

Volume

63

Issue

9

Pub Type

Journals

Download Paper

https://doi.org/10.1007/s11837-011-0161-8

Local Download

Keywords

Plastic Deformation, Crystal Plasticity Modeling, Electron Backscatter Diffraction (EBSD), X-ray Diffraction (XRD), Titanium

Citation

Yang, Y. , Wang, L. , Zambaldi, C. , Eisenlohr, P. , Barabash, R. , Liu, W. , Stoudt, M. , Crimp, M. and Bieler, T. (2011), Experimental characterization and crystal plasticity finite element modeling of heterogeneous deformation in commercial purity titanium, JOM Journal of the Minerals Metals and Materials Society, [online], https://doi.org/10.1007/s11837-011-0161-8, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=908773 (Accessed April 25, 2024)