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It must be noted that a hydrodynamic limit of the penetration depth
(calculated according to the hydrodynamic penetration theory [2] using both
the projectile length and its density – a target density ratio) for the VNZh-
90 alloy projectile with the length of
l
0
= 500
mm, in the case of a steel
target is about 740 mm. Therefore, the penetration depth at
v
0
= 2000
m/s
is additionally about 10% less than its hydrodynamic limit.
Fig. 4 shows the material density fields at different time, which
illustrates the penetration of a steel target by the VNZh-90 alloy rod-
shaped projectiles with the length of
l
0
= 500
mm and a typical yield
strength (
σ
Y
= 1000
MPa) at the initial velocities
v
0
= 1400
m/s (Fig. 4,
a
)
and
v
0
= 2000
m/s (Fig. 4,
b
). The presented results prove that in both
Fig. 4. Steel target penetration by the VNZh-90 alloy elongated projectiles with the
yield strength of 1000 MPa at different initial velocities:
а
—
v
0
= 1400
m/s;
b
—
v
0
= 2000
m/s
76 ISSN 0236-3941. HERALD of the BMSTU Series “Mechanical Engineering”. 2015. No. 1