Ordering and the micromechanics of Ti-7Al

Anna Radecka; James Coakley; Ian P Jones; David Rugg; Trevor Lindley; David Dye

doi:10.1016/j.msea.2015.09.070

Ordering and the micromechanics of Ti-7Al

Anna Radecka, James Coakley, Ian P Jones, David Rugg, Trevor Lindley, David Dye

Metallurgy and Materials

Research output: Contribution to journal › Article › peer-review

11 Citations (Scopus)

160 Downloads (Pure)

Abstract

The evolution of intergranular lattice strain in the α titanium alloy Ti-7Al wt.% was characterised using in situ time-of-flight (TOF) neutron diffraction during room temperature tensile loading. Samples were aged to promote ordering and the formation of nanometre-scale a₂ (Ti₃Al). On ageing, at 550 °C and 625 °C, dislocations were observed to travel in pairs, and in planar arrays, which has been attributed to the presence of ordering. A slight change in c/a was observed, from 1.6949 to 1.6945, and a slight increase in the macroscopic modulus. However, no changes were observed in the residual lattice strains, which are the grain-orientation average elastic strains produced by plasticity. Therefore it is inferred that the changes in deformation mechanisms caused by ordering that result in an enhanced vulnerability to dwell fatigue affect primarily the extent of slip localisation. The overall strain distributions between grains in different orientations is not changed.

Original language	English
Journal	Materials Science and Engineering A
Early online date	21 Sept 2015
DOIs	https://doi.org/10.1016/j.msea.2015.09.070
Publication status	E-pub ahead of print - 21 Sept 2015

Keywords

Titanium alloys
Neutron scattering
Ordering transition

Access to Document

10.1016/j.msea.2015.09.070

Radecka_et_al_2015_Ordering_micromechanics_Ti_7Al_Materials_Science_Engineering_A
After an embargo period, this document is subject to the terms of a Creative Commons Non-Commercial No Derivatives license. Checked October 2015
Accepted author manuscript, 13.3 MBLicence: Creative Commons: Attribution-NonCommercial-NoDerivs (CC BY-NC-ND)

http://linkinghub.elsevier.com/retrieve/pii/S0921509315304068

Cite this

@article{2a421c6176514ff0b82ad78e76f7a754,

title = "Ordering and the micromechanics of Ti-7Al",

abstract = "The evolution of intergranular lattice strain in the α titanium alloy Ti-7Al wt.% was characterised using in situ time-of-flight (TOF) neutron diffraction during room temperature tensile loading. Samples were aged to promote ordering and the formation of nanometre-scale a2 (Ti3Al). On ageing, at 550 °C and 625 °C, dislocations were observed to travel in pairs, and in planar arrays, which has been attributed to the presence of ordering. A slight change in c/a was observed, from 1.6949 to 1.6945, and a slight increase in the macroscopic modulus. However, no changes were observed in the residual lattice strains, which are the grain-orientation average elastic strains produced by plasticity. Therefore it is inferred that the changes in deformation mechanisms caused by ordering that result in an enhanced vulnerability to dwell fatigue affect primarily the extent of slip localisation. The overall strain distributions between grains in different orientations is not changed.",

keywords = "Titanium alloys, Neutron scattering, Ordering transition",

author = "Anna Radecka and James Coakley and Jones, {Ian P} and David Rugg and Trevor Lindley and David Dye",

year = "2015",

month = sep,

day = "21",

doi = "10.1016/j.msea.2015.09.070",

language = "English",

journal = "Materials Science and Engineering A",

issn = "0921-5093",

publisher = "Elsevier",

}

TY - JOUR

T1 - Ordering and the micromechanics of Ti-7Al

AU - Radecka, Anna

AU - Coakley, James

AU - Jones, Ian P

AU - Rugg, David

AU - Lindley, Trevor

AU - Dye, David

PY - 2015/9/21

Y1 - 2015/9/21

N2 - The evolution of intergranular lattice strain in the α titanium alloy Ti-7Al wt.% was characterised using in situ time-of-flight (TOF) neutron diffraction during room temperature tensile loading. Samples were aged to promote ordering and the formation of nanometre-scale a2 (Ti3Al). On ageing, at 550 °C and 625 °C, dislocations were observed to travel in pairs, and in planar arrays, which has been attributed to the presence of ordering. A slight change in c/a was observed, from 1.6949 to 1.6945, and a slight increase in the macroscopic modulus. However, no changes were observed in the residual lattice strains, which are the grain-orientation average elastic strains produced by plasticity. Therefore it is inferred that the changes in deformation mechanisms caused by ordering that result in an enhanced vulnerability to dwell fatigue affect primarily the extent of slip localisation. The overall strain distributions between grains in different orientations is not changed.

AB - The evolution of intergranular lattice strain in the α titanium alloy Ti-7Al wt.% was characterised using in situ time-of-flight (TOF) neutron diffraction during room temperature tensile loading. Samples were aged to promote ordering and the formation of nanometre-scale a2 (Ti3Al). On ageing, at 550 °C and 625 °C, dislocations were observed to travel in pairs, and in planar arrays, which has been attributed to the presence of ordering. A slight change in c/a was observed, from 1.6949 to 1.6945, and a slight increase in the macroscopic modulus. However, no changes were observed in the residual lattice strains, which are the grain-orientation average elastic strains produced by plasticity. Therefore it is inferred that the changes in deformation mechanisms caused by ordering that result in an enhanced vulnerability to dwell fatigue affect primarily the extent of slip localisation. The overall strain distributions between grains in different orientations is not changed.

KW - Titanium alloys

KW - Neutron scattering

KW - Ordering transition

U2 - 10.1016/j.msea.2015.09.070

DO - 10.1016/j.msea.2015.09.070

M3 - Article

SN - 0921-5093

JO - Materials Science and Engineering A

JF - Materials Science and Engineering A

ER -

Ordering and the micromechanics of Ti-7Al

Abstract

Keywords

Access to Document

Fingerprint

Cite this