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7 Impact Resistance of Armor Steel/Ceramic/UHPCC Layered …
The ballistic efficiency factor has a great significance for designers since it
connects both the mass and thickness efficiency factors. Values of 1.0 or above for
E t and E m indicate that the armor steel under evaluation is thinner and lighter than
the equivalent reference material, i.e., UHPCC at present, under the identical specified threat. Therefore, it can be drawn that, the armor steel/UHPCC in the protective
structures of civil engineering can more effectively reduce the weight or improve the
impact resistance of the structures.
In view of the fact that the composite target with 8 mm-thick armor steel
plate obtained the maximum ballistic efficiency factor, the NP500_8mm/UHPCC
composite target with a striking velocity of 481 m/s is further simulated to quantitatively compare the ballistic performance of the current two kinds of composite
targets. The simulated P RES of NP500_8mm/UHPCC composite target (481 m/s) is
6 mm, which is only 25% of that of NP450_8mm/UHPCC composite target. In this
scenario, the calculated E t , E m , and q
2 are 19.09, 6.14 and 117.79 while those are
16.84, 5.42 and 91.28 for NP450_8mm/UHPCC composite target, respectively.
7.4 Summary
The medium caliber projectile impact resistance of armor steel/ceramic/UHPCC
layered composite targets against 30CrMnSiNi2A steel projectiles are studied both
experimentally and numerically. By calibrating the JC constitutive model parameters of the present 10CrNi3MoV21A, NP450 and NP500 armor steel, the numerically predicted penetration depth, residual length of the projectile, as well as the
abrasion and damage of projectiles and armor steel plates were compared with the
experimental observations. The main conclusions are summarized as follows:
(1) Compared with the NSC target, UHPCC and the present 10CrNi3MoV21A
armor steel/SiC ceramic/UHPCC composite targets were experimentally and
numerically verified to be effective in resisting the projectile penetration. For
example, up to about 77.4% of the DOP into the NSC target was reduced by
the 11 mm SiC ceramic/UHPCC composite target.
(2) Rigid and eroding penetration regimes were revealed experimentally, and the
most severe abrasion of projectile occurred in scenario C11. Meanwhile, with
almost the same thickness, SiC ceramic plate was verified to possess superior
impact resistance to the 10CrNi3MoV21A armor steel plate considering both
thickness and mass efficiency factors.
(3) The armor steel/ceramic/UHPCC composite structure was verified to be
a promising protective configuration with excellent ballistic performance
including high impact resistance, light weight and low thermal conductivity.
(4) NP450/UHPCC and NP500/UHPCC composite targets have a much more
outstanding impact resistance regarding DOP and crater diameter than UHPCC
target, and NP500/UHPCC composite target exhibits the best impact resistance.
7 Impact Resistance of Armor Steel/Ceramic/UHPCC Layered …
The ballistic efficiency factor has a great significance for designers since it
connects both the mass and thickness efficiency factors. Values of 1.0 or above for
E t and E m indicate that the armor steel under evaluation is thinner and lighter than
the equivalent reference material, i.e., UHPCC at present, under the identical specified threat. Therefore, it can be drawn that, the armor steel/UHPCC in the protective
structures of civil engineering can more effectively reduce the weight or improve the
impact resistance of the structures.
In view of the fact that the composite target with 8 mm-thick armor steel
plate obtained the maximum ballistic efficiency factor, the NP500_8mm/UHPCC
composite target with a striking velocity of 481 m/s is further simulated to quantitatively compare the ballistic performance of the current two kinds of composite
targets. The simulated P RES of NP500_8mm/UHPCC composite target (481 m/s) is
6 mm, which is only 25% of that of NP450_8mm/UHPCC composite target. In this
scenario, the calculated E t , E m , and q
2 are 19.09, 6.14 and 117.79 while those are
16.84, 5.42 and 91.28 for NP450_8mm/UHPCC composite target, respectively.
7.4 Summary
The medium caliber projectile impact resistance of armor steel/ceramic/UHPCC
layered composite targets against 30CrMnSiNi2A steel projectiles are studied both
experimentally and numerically. By calibrating the JC constitutive model parameters of the present 10CrNi3MoV21A, NP450 and NP500 armor steel, the numerically predicted penetration depth, residual length of the projectile, as well as the
abrasion and damage of projectiles and armor steel plates were compared with the
experimental observations. The main conclusions are summarized as follows:
(1) Compared with the NSC target, UHPCC and the present 10CrNi3MoV21A
armor steel/SiC ceramic/UHPCC composite targets were experimentally and
numerically verified to be effective in resisting the projectile penetration. For
example, up to about 77.4% of the DOP into the NSC target was reduced by
the 11 mm SiC ceramic/UHPCC composite target.
(2) Rigid and eroding penetration regimes were revealed experimentally, and the
most severe abrasion of projectile occurred in scenario C11. Meanwhile, with
almost the same thickness, SiC ceramic plate was verified to possess superior
impact resistance to the 10CrNi3MoV21A armor steel plate considering both
thickness and mass efficiency factors.
(3) The armor steel/ceramic/UHPCC composite structure was verified to be
a promising protective configuration with excellent ballistic performance
including high impact resistance, light weight and low thermal conductivity.
(4) NP450/UHPCC and NP500/UHPCC composite targets have a much more
outstanding impact resistance regarding DOP and crater diameter than UHPCC
target, and NP500/UHPCC composite target exhibits the best impact resistance.