The tensile behaviour of near a Ti3Al2.5 V alloy,conceived for applications in aerospace and automotive engineering,is characterized from quasi-static to high strain rates.The material is found to present noticeable s...The tensile behaviour of near a Ti3Al2.5 V alloy,conceived for applications in aerospace and automotive engineering,is characterized from quasi-static to high strain rates.The material is found to present noticeable strain rate sensitivity.The dynamic true strain rate in the necking cross-section reaches values up to ten times higher than the nominal strain rate.It is also observed that beyond necking the dynamic true stress-strain curves present limited rate dependence.The experimental results at different strain rates are used to determine a suitable constitutive model for finite element simulations of the dynamic tensile tests.The model predicts the experimentally macroscopic force-time response,true stress-strain response and effective strain rate evolution with good agreement.展开更多
Materials innovation calls for an integrated framework combining physics-based modelling and data-driven informatics.A dislocation-based constitutive model accounting for both transformation-induced plasticity(TRIP)an...Materials innovation calls for an integrated framework combining physics-based modelling and data-driven informatics.A dislocation-based constitutive model accounting for both transformation-induced plasticity(TRIP)and twinning-induced plasticity(TWIP)was built to interpret the mechanical characteristics of metastable titanium alloys.Particular attention was placed on quantitatively understanding the composition-sensitive phase stability and its influence on the underlying deformation mechanism.For this purpose,a pseudoelastic force balance incorporating thermodynamics and micromechanics was applied to calculate the energy landscapes ofβ→α″martensitic transformation,{332}(113)twinning and dislocation slip.Extensive material data were probed,computed and fed to the model.Our results revealed that TRIP and TWIP may operate simultaneously because of the presence of a noticeably overlapped energy domain,and confirmed{332}(113)twinning is an energetically favourable deformation mechanism.The model validation further unveiled that the activation ofβ→α″transition remarkably enhances the strain-hardening and plasticity,even though the dynamically formedα″volume fraction is much less than that of deformation twinning.Our work suggests that the synchronised physical metallurgy and data-driven strategy allows to identify the compositional scenarios for developing high-performance engineering alloys.展开更多
文摘The tensile behaviour of near a Ti3Al2.5 V alloy,conceived for applications in aerospace and automotive engineering,is characterized from quasi-static to high strain rates.The material is found to present noticeable strain rate sensitivity.The dynamic true strain rate in the necking cross-section reaches values up to ten times higher than the nominal strain rate.It is also observed that beyond necking the dynamic true stress-strain curves present limited rate dependence.The experimental results at different strain rates are used to determine a suitable constitutive model for finite element simulations of the dynamic tensile tests.The model predicts the experimentally macroscopic force-time response,true stress-strain response and effective strain rate evolution with good agreement.
基金The authors would like to acknowledge Rolls-Royce plc for their continuing support through the Solid Mechanics University Technology Centre at the University of Oxford.X.Q.L.acknowledges the Swedish Research Council(grant agreement no.2020-03736)N.P.acknowledges the UK Royal Academy of Engineering for Chair Sponsorship.
文摘Materials innovation calls for an integrated framework combining physics-based modelling and data-driven informatics.A dislocation-based constitutive model accounting for both transformation-induced plasticity(TRIP)and twinning-induced plasticity(TWIP)was built to interpret the mechanical characteristics of metastable titanium alloys.Particular attention was placed on quantitatively understanding the composition-sensitive phase stability and its influence on the underlying deformation mechanism.For this purpose,a pseudoelastic force balance incorporating thermodynamics and micromechanics was applied to calculate the energy landscapes ofβ→α″martensitic transformation,{332}(113)twinning and dislocation slip.Extensive material data were probed,computed and fed to the model.Our results revealed that TRIP and TWIP may operate simultaneously because of the presence of a noticeably overlapped energy domain,and confirmed{332}(113)twinning is an energetically favourable deformation mechanism.The model validation further unveiled that the activation ofβ→α″transition remarkably enhances the strain-hardening and plasticity,even though the dynamically formedα″volume fraction is much less than that of deformation twinning.Our work suggests that the synchronised physical metallurgy and data-driven strategy allows to identify the compositional scenarios for developing high-performance engineering alloys.
