Determination of Ti-6242 α and β slip properties using micro-pillar test and computational crystal plasticity. (October 2016)

• Record Type: Journal Article
• Authors: Zhang, Zhen; Jun, Tea-Sung; Britton, T. Benjamin; Dunne, Fionn P.E.
• Is Part Of: Journal of the mechanics and physics of solids. Volume 95(2016:Oct.)
• Page Start: 393
• Page End: 410
• Publication Date: 2016-10
• Subjects: β phase -- Ti-6242 -- Micro-compression -- Stress relaxation -- Strain rate sensitivity -- Slip transfer -- Burgers orientation relationship; Mechanics, Applied -- Periodicals; Solids -- Periodicals; Mechanics -- Periodicals; Mécanique appliquée -- Périodiques; Solides -- Périodiques; Mechanics, Applied; Solids; Periodicals; 531.05
• DOI: 10.1016/j.jmps.2016.06.007
• Languages: English
• ISSNs: 0022-5096

Abstract

Abstract: The properties and behaviour of an α−β colony Ti-6242 alloy have been investigated at 20 °C utilising coupled micro-pillar stress relaxation tests and computational crystal plasticity. The β-phase slip strength and intrinsic slip system strain rate sensitivity have been determined, and the β-phase shown to have stronger rate sensitivity than that for the α phase. Close agreement of experimental observations and crystal plasticity predictions of micro-pillar elastic-plastic response, stress relaxation, slip activation in both α and β-phases, and strain localisation within the α−β pillars with differing test strain rate, β morphology, and crystal orientations is achieved, supporting the validity of the properties extracted. The β-lath thickness is found to affect slip transfer across the α−β−α colony, but not to significantly change the nature of the slip localisation when compared to pure α-phase pillars with the same crystallographic orientation. These results are considered in relation to rate-dependent deformation, such as dwell fatigue, in complex multiphase titanium alloys.