Characterization of the Microstructure, Local Macro-Texture and Residual Stress Field of Commercially Pure Titanium Grade Prepared by CONFORM ECAP

0500351 - ÚJF 2019 RIV CH eng J - Článek v odborném periodiku
Németh, Gergely - Fekete-Horváth, Klaudia - Hervoches, Charles - Cejpek, P. - Palán, J. - Duchek, M. - Mathis, Kristián
Characterization of the Microstructure, Local Macro-Texture and Residual Stress Field of Commercially Pure Titanium Grade Prepared by CONFORM ECAP.
Metals. Roč. 8, č. 12 (2018), č. článku 1000. E-ISSN 2075-4701
Grant CEP: GA ČR GB14-36566G; GA MŠMT EF16_013/0001794; GA MŠMT LM2015056
Institucionální podpora: RVO:61389005
Klíčová slova: titanium * CONFORM * ECAP * residual * strain * stress * EBSD * texture
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 2.259, rok: 2018

The paper investigated the residual strain and stress distribution, microstructure, and macro-texture along the transverse direction of commercially pure titanium grade 2 samples prepared by the CONFORM ECAP technique. This method belongs to the severe plastic deformation methods. Hence, it could be assumed that residual stress fields would be present in the work-pieces. Residual stresses cannot be directly measured. Thus, neutron diffraction measurements, Electron back-scatter diffraction (EBSD) investigations, and local X-ray macro-texture measurements were performed in different regions of the sample to determine the data for the residual stress calculation. The calculation was based on the modified Kroner model. Neutron diffraction strain scans and residual stress calculations revealed that symmetrical residual strain and stress gradients with compression character were present in the axial and hoop direction after one and two passes. Asymmetric distribution of the residual strains and stresses remained after the third pass of the CONFORM ECAP. EBSD investigations showed that after the first pass, significant grain refinement occurred. However, further passes did not cause any dramatic grain refinement. X-ray texture measurements revealed that local macro-texture was dependent on the number of passes of the CONFORM ECAP and on the investigated area in the samples.
Trvalý link: http://hdl.handle.net/11104/0292464