Ramp wave experiments on the Sandia Z accelerator provide a different approach to study the rapid compression response of materials at pressures, temperatures, and stress or strain rates not attainable in conventional shock experiments. Due to its shockless nature, the ramp wave experiment is often termed as an isentropic (or quasi-isentropic) compression experiment (ICE) and the analysis of ICE has been focused on determination of the isentropes. One objective of the current study is to show that ramp wave experiment can be used as a much more general material characterization tool for studying material behavior under high strain rates and pressures. The second objective is to suggest practical methodology to design the experiment and analyze experimental data. Numerical simulations were used to achieve these objectives. It is demonstrated that the ramp wave experiment is essentially a controlled-strain-rate material test. The strain rate can be varied through the rise time and shape of the ramp wave. The resultant stress-strain relation is a specific relation for a specific strain-rate history. The isentrope, which is a limiting case of such relations, may be approximated through a very low strain-rate loading path. Because of the rate dependence of the material behavior, each material point experiences different strain-rate loading paths. Lagrangian analysis requires information pertinent to a local Lagrangian material point. This information may be obtained through a pair of wave profiles measured at two very close, but essentially the same, Lagrangian points.

1.
J. L.
Ding
,
J. Mech. Phys. Solids
56
,
237
(
2006
).
2.
J. N.
Johnson
and
L. M.
Barker
,
J. Appl. Phys.
40
,
4321
(
1969
).
3.
L. C.
Chhabildas
and
J. R.
Asay
,
J. Appl. Phys.
50
,
2749
(
1979
).
4.
J. W.
Swegle
and
D. E.
Grady
,
J. Appl. Phys.
58
,
692
(
1985
).
5.
L. M.
Barker
and
R. E.
Hollenbach
,
J. Appl. Phys.
43
,
4669
(
1972
).
6.
J. R.
Asay
, in
Shock Compression of Condensed Matter, Furnish
, edited by
L. C.
Chhabildas
and
R. S.
Hixson
(
American Institute of Physics
,
New York
,
2000
), pp.
261
266
.
7.
C. A.
Hall
,
J. R.
Asay
,
M. D.
Knudson
,
W. A.
Stygar
,
R. B.
Spielman
,
T. D.
Pointon
,
D. B.
Reisman
,
A.
Toor
, and
R. C.
Cauble
,
Rev. Sci. Instrum.
72
,
3587
(
2001
).
8.
L. E.
Malvern
,
Introduction to the Mechanics of a Continuous Medium
(
Prentice-Hall
,
Englewood Cliffs, NJ
,
1969
).
9.
D. C.
Wallace
,
Phys. Rev. B
22
,
1477
(
1980
).
10.
D. C.
Wallace
,
Phys. Rev. B
24
,
5607
(
1981
).
11.
Y. M.
Gupta
, COPS wave propagation code,
SRI International
, Menlo Park, CA.
12.
M. L.
Wilkins
, in
Methods in Computational Physics
, edited by
B.
Alder
,
S.
Fernbach
, and
M.
Rotenberg
, (
Academic
,
New York
,
1964
), Vol.
3
, pp.
211
263
.
13.
R. T.
Walsh
, in
Dynamic Response of Materials to Intense Impulsive Loading
, edited by
P. C.
Chou
and
A. K.
Hopkins
(
Air Force Materials Laboratory
,
OH
,
1973
), pp.
363
403
.
14.
T. J.
Ahrens
and
G. E.
Duvall
,
J. Geophys. Res.
71
,
4349
(
1966
).
15.
C. A.
Hall
Phys. Plasmas
7
,
2069
(
2000
).
16.
D. B.
Reisman
,
A.
Toor
,
R. C.
Cauble
,
C. A.
Hall
,
J. R.
Asay
,
M. D.
Knudson
, and
M. D.
Furnish
,
J. Appl. Phys.
89
,
1625
(
2001
).
17.
J. B.
Aidun
and
Y. M.
Gupta
,
J. Appl. Phys.
69
,
6998
(
1991
).
18.
R.
Fowles
and
R. F.
Williams
,
J. Appl. Phys.
41
,
360
(
1970
).
19.
J. L.
Ding
and
S. R.
Lee
,
Int. J. Plast.
4
,
149
(
1988
).
20.
K. T.
Lorentz
,
M. J.
Edwards
,
S. G.
Glendinning
,
A. F.
Jankowski
,
J.
McNaney
,
S. M.
Pollaine
, and
B. A.
Remington
,
Phys. Plasmas
12
,
056309
(
2005
).
You do not currently have access to this content.