Three-dimensional characterisation and simulation of deformation and damage during Taylor impact in PTFE

18th APS-SCCM; 24th AIRAPT

Resnyansky, A.D.^1 ; McDonald, S.A.^2 ; Withers, P.J.^2 ; Bourne, N.K.^2,3 ; Millett, J.C.F.^3 ; Brown, E.N.^4 ; Rae, P.J.^4

Weapons and Countermeasures Division, DSTO, PO Box 1500, Edinburgh

SA

5111, Australia^1

School of Materials, University of Manchester, Manchester

M13 9PL, United Kingdom^2

AWE, Aldermaston, Reading

RG7 4PR, United Kingdom^3

Los Alamos National Laboratory, Los Alamos

NM

87545, United States^4

关键词: Crystalline domains;    Cylindrical samples;    Deformation and damages;    High pressure loading;    High-pressure phase transitions;    Phase transition kinetics;    Polytetrafluoroethylene (PTFE);    X ray microtomography;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/18/182035/pdf
DOI  :  10.1088/1742-6596/500/18/182035

来源: IOP

【 摘 要 】

The current work presents Taylor impact experiments interrogating the effect of dynamic, high-pressure loading on polytetrafluoroethylene (PTFE). In particular, X-ray microtomography has been used to characterise the damage imparted to cylindrical samples due to impact at different velocities. Distinct regions of deformation are present and controlled by fracture within the polymer, with the extent of the deformed region and increasing propagation of fractures from the impact face showing a clear trend with increasing impact velocity. A two-phase rate sensitive strength model is implemented in the CTH hydrocode and used for simulation of the problem. The high-pressure phase transition of PTFE into Phase III within the crystalline domains from the polymer at normal conditions is managed by suitable phase transition kinetics within the model. The experimental observations are discussed with respect to the multi-phase model hydrocode predictions of the shock response from Taylor impact simulations. The damage and its progress are shown to correlate well with the onset of the phase transition and its evolution following the impact velocity increase.