The integration of a high-hardness steel armor plate inside the bodywork of a vehicle may result in a decrease in the overall ballistic resistance. This phenomenon is referred to as the bodywork effect. The effect was examined for a 5.56×45mm North Atlantic Treaty Organization (NATO) Ball projectile. Previously reported experimental work has confirmed the numerically based assumption that the bodywork effect was due to the flattening of the tip of the projectile upon perforation of the frontal bodywork plate prior to hitting the integrated armor. The amount of qualitative and quantitative experimental data has now been extended. In order to eliminate the data dispersion observed after perforating the bodywork, an adapted projectile geometry with a truncated nose was fired directly against the armor plate. Ballistic testing also involved firing a soft-core 5.56×45mm projectile for which a similar mechanism was observed. A finite element code was used to simulate the impact process for the different types of projectiles. The parameters of the selected strength and failure models were experimentally determined for the high-hardness armor plate. As to the ballistic limit velocity and plugging morphology there is a good correspondence between the experimental and computed results. Nevertheless, an improved failure model is necessary to get satisfactory computed residual projectile velocities.

1.
NATO, 2004, “
Protection Levels for Occupants of Logistic and Light Armoured Vehicles
,” NATO Standardization Agency, Annex A, STANAG 4569.
2.
Doig
,
A.
, 1998,
Military Metallurgy
,
British Crown/MOD
,
London, UK
, p.
11
.
3.
Meyer
,
L.
, 2008, “
Zur Rolle der Zähigkeit bei Blast-Belastung
,”
Proceedings of the Union’s 2nd Tag der Ballistik
, Ulm, Germany, Apr. 17.
4.
Adams
,
B.
, 2003, “
Simulation of Ballistic Impacts on Armored Civil Vehicles
,” MS thesis, Eindhoven University of Technology, Eindhoven, The Netherlands, pp.
65
68
.
5.
Dey
,
S.
,
Børvik
,
T.
,
Hopperstad
,
O. S.
,
Leinum
,
J. R.
, and
Langseth
,
M.
, 2004, “
The Effect of Target Strength on the Perforation of Steel Plates Using Three Different Projectile Nose Shapes
,”
Int. J. Impact Eng.
0734-743X,
30
, pp.
1005
1038
.
6.
Zukas
,
J. A.
,
Nicholas
,
T.
,
Swift
,
H. F.
,
Greszczuk
,
L. B.
, and
Curran
,
D. R.
, 1982,
Impact Dynamics
,
Wiley
,
New York
, p.
204
.
7.
Coghe
,
F.
,
Kestelyn
,
B.
, and
Pirlot
,
M.
, 2008, “
Experimental Validation of the Origin of the Bodywork Effect (K-effect) in the Up-Armouring of Civil and Military Vehicles
,”
Proceedings of the 24th International Symposium on Ballistics
, New Orleans, LA, pp.
421
429
.
8.
ThyssenKrupp, 2007, “
Secure Ballistic Steels: Processing Recommendations
,” ThyssenKrupp Steel AG.
9.
Hogg
,
I. V.
, ed., 1986,
Jane’s Infantry Weapons
,
Jane’s Publishing Company Ltd.
,
London, UK
, pp.
362
363
.
10.
NATO, 2003, “
Ballistic Test Method for Personal Armour Materials and Combat Clothing
,” NATO Standardization Agency STANAG 2920.
11.
Maldague
,
M.
, 2008, “
Evaluation of Some Methods in Order to Determine V50
,”
Proceedings of the Personal Armour Systems Symposium
, Brussels, Belgium.
12.
Kolsky
,
H.
, 1949, “
An Investigation of the Mechanical Properties of Materials at Very High Loading Rates
,”
Proc. Phys. Soc. London
0370-1328,
B62
, pp.
676
700
.
13.
Hopkinson
,
B.
, 1914, “
A Method of Measuring the Pressure Produced in the Detonation of High Explosives or by the Impact of Bullets
,”
Philos. Trans. R. Soc. London, Ser. A
0962-8428,
213
, pp.
437
456
.
14.
Berkovic
,
L.
,
Ryckaert
,
R.
,
Chabotier
,
A.
,
Gilson
,
L.
,
Coghe
,
F.
, and
Rabet
,
L.
, “
Modeling of High Temperature Hopkinson Tests on AA5083 and Ti6Al4V
,”
Proceedings of DYMAT 2009-9th International Conference on the Mechanical and Physical Behaviour of Materials Under Dynamic Loading
, Brussels, Belgium, pp.
1663
1668
.
15.
Lienhard
,
J. H.
, IV
, and
Lienhard
,
J. H. V.
, 2008,
A Heat Transfer Textbook
,
Phlogiston Press
,
Cambridge, MA
, pp.
220
235
.
16.
Ryckaert
,
R.
, 2008, “
Bepalen van Materiaalparameters bij Hoge Temperatuur met de Hopkinson Opstelling
,” MS thesis, Royal Military Academy, Brussels, Belgium.
17.
Johnson
,
G. R.
, and
Cook
,
W. H.
, 1983, “
A Constitutive Model and Data for Metals Subjected to Large Strains, High Strain Rates and High Temperatures
,”
Proceedings of the Seventh International Symposium on Ballistics
, The Hague, The Netherlands, pp.
541
547
.
18.
Meyers
,
M.
, 1994,
Dynamic Behavior of Materials
,
Wiley
,
New York
, p.
377
.
19.
Bai
,
Y.
, and
Dodd
,
B.
, 2004,
Adiabatic Shear Localization: Occurrence, Theories and Applications
,
ISL
,
Saint Louis, France
, p.
10
.
20.
Teng
,
X.
, and
Wierzbicki
,
T.
, 2006, “
Evaluation of Six Fracture Models in High Velocity Perforation
,”
Eng. Fract. Mech.
0013-7944,
73
, pp.
1653
1678
.
21.
Wierzbicki
,
T.
,
Bao
,
Y.
,
Lee
,
Y.
, and
Bai
,
Y.
, 2005, “
Calibration and Evaluation of Seven Fracture Models
,”
Int. J. Mech. Sci.
0020-7403,
47
, pp.
719
743
.
22.
Johnson
,
G. R.
, and
Cook
,
W. H.
, 1985, “
Fracture Characteristics of Three Metals Subjected to Various Strains, Strain Rates, Temperatures and Pressures
,”
Eng. Fract. Mech.
0013-7944,
21
(
1
), pp.
31
48
.
23.
Buchar
,
J.
,
Voldrich
,
J.
,
Rolc
,
S.
, and
Lisy
,
J.
, 2002, “
Ballistic Performance of the Dual Hardness Armour
,”
Proceedings of the 20th International Symposium on Ballistics
, Orlando, FL, pp.
421
429
.
24.
Backman
,
M. E.
, 1976, “
Terminal Ballistics
,” Naval Weapons Center, NTIS Report No. AD-A021 833.
25.
Lambert
,
J. P.
, 1978, “
A Residual Velocity Predictive Model for Long Rod Penetrators
,” Aberdeen Proving Ground, BRL, Report No. ARBRL-MR-02828.
26.
Zukas
,
J. A.
, and
Walters
,
W. P.
, eds., 1998,
Explosive Effects and Applications
,
Springer-Verlag
,
New York
, pp.
91
93
.
27.
Los Alamos Scientific Laboratory, 1969, “
Selected Hugoniots
,” Los Alamos Scientific Laboratory, Los Alamos, NM, Report No. LA-4167-MS.
28.
Bao
,
Y.
, and
Wierzbicki
,
T.
, 2005, “
On the Cut-Off Value of Negative Triaxiality for Fracture
,”
Eng. Fract. Mech.
0013-7944,
72
, pp.
1049
1069
.
29.
Bao
,
Y.
, and
Wierzbicki
,
T.
, 2004, “
On Fracture Locus in the Equivalent Strain and Stress Triaxiality Space
,”
Int. J. Mech. Sci.
0020-7403,
46
, pp.
81
98
.
30.
Totten
,
G. E.
, ed., 2007,
Steel Heat Treatment: Metallurgy and Technologies
,
CRC Press
,
Boca Raton, FL
, pp.
357
359
.
31.
Dieter
,
G. E.
, 1986,
Mechanical Metallurgy
,
3rd ed.
,
McGraw-Hill
,
New York
, p.
489
.
You do not currently have access to this content.