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When the projectile velocity rises up to
v
0
= 2000
m/s, a rather
high yield strength of the projectile material (
σ
Y
= 1000
MPa) does not
cause any noticeable deceleration of the remaining part of the projectile
(see Fig. 6). The penetration velocity
v
0
— initial velocity
v
0
ratio at
v
0
= 2000
m/s turns out to be significantly higher than at
v
0
= 2000
m/s,
which apparently arises from the reduction of the target strength effect
during the increase of the interaction velocity. Contact stress
σ
zc
at the target
interface increases almost twofold (approximately from 4 up to 7,5 GPa)
when the interaction velocity rises from 1400 to 2000 m/s.
In the both cases this stress is much higher than the yield strength
of the projectile material which provides conditions for a hydrodynamic
penetration mode.
In general, the results of the numerical computation show that the
material strength of the elongated projectiles made of a high-density alloy
has an insignificant impact on their penetration at the interaction velocities
of 1500 m/s and higher. Therefore, it does not seem to require taking special
measures for increasing material strength up to the maximal possible limit
while developing the production process of the high-density rod-shaped
projectiles. On the contrary, the analysis showns that a very high yield
strength of the elongated projectile material may result even in a certain
decrease of the projectile penetration.
According to the results of the numerical simulation, the dependence
of the projectile penetration depth on its material yield strength is
nonmonotonic and has a poorly defined extremum corresponding to the
maximal penetration.
The work was fulfilled with the financial support of the Russian Ministry
of Education and Science. It is a part of the basic component of the state
government task for higher educational establishments.
REFERENCES
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physics of explosion and shock]. Moscow, MGTU im. N.E. Baumana Publ., 2000.
516 p.
[2] Sagomonyan
A.Ya. Pronikanie [Penetration]. Moscow, MGU Publ., 1974. 300 p.
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[High-speed interaction of bodies]. Novosibirsk, Izd. SO RAN Publ., 1999. 600 p.
[4] Alekseevskiy V.P. On the penetration of the rod into the target at high velocity.
Fiz.
Goreniya Vzryva
[Combust., Explos., Shock Waves], 1966, vol. 2, no. 2, pp. 99–106
(in Russ.).
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J. Mech. Phys. Solids
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ISSN 0236-3941. HERALD of the BMSTU Series “Mechanical Engineering”. 2015. No. 1 79