Rong-cheng Yi,Li-kui Yin,Jian-ru Wang,Zhi-gang Chen,Di-qi Hu

National Defense Key Laboratory of Underground Damage Technology,North University of China,Taiyuan 030051,China

Study on the performance of ceramic composite projectile penetrating into ceramic composite target

Rong-cheng Yi*,Li-kui Yin**,Jian-ru Wang***,Zhi-gang Chen,Di-qi Hu

National Defense Key Laboratory of Underground Damage Technology,North University of China,Taiyuan 030051,China

A R T I C L E I N F O

Article history:

19 April 2017

Accepted 22 May 2017

Available online 26 May 2017

Ceramic

Composite projectile

Penetration

Composite target

Test

In order to study the performance of ceramic composite projectile penetrating into ceramic composite target,the contrast test and numerical simulations of the penetration of standard projectile and the ceramic composite projectile into a ceramic composite target were conducted.The results show that the penetration performance of ceramic composite projectile is obvious superior to that of standard projectile for ceramic composite target.The ceramic nose of ceramic composite projectile fully destroys the ceramic panels anterior to its following armor-piercing projectile body,thus maintaining the penetration ability of the following armor-piercing projectile body.

?2017 Published by Elsevier Ltd.This is an open access article under the CC BY-NC-ND license(http:// creativecommons.org/licenses/by-nc-nd/4.0/).

1.Introduction

Ceramic composite armoras one of the most effective protection armors is widely used for various types of military vehicles protection.When penetrating into ceramic composite armor,the projectile body of active small-caliber armor-piercing projectile against light armor may be fractured and then crushed due to the in fluence of ceramic panel,and its posture may be de flected, leading to its inef ficiency in armor penetration[1].Therefore,it is necessary to study the development of small-caliber armorpiercing projectile with lethal effect against ceramic composite armor.

Ceramic has long been used for projectile-proof protection,but has relatively less been studied as the penetration body.Nechitailo et al.[2,3]studied the penetration of AD-85 ceramic rods into aluminum plate,steel plate and tungsten plate,and the penetration ofceramic-steelcomposite components concrete through numerical simulation.Li et al.[4]studied the performance of ceramic and alloy steel cylindrical components to penetrate into ceramic/composite targets,and indicated that the damage of the ceramic component to the ceramic/composite target is much greater than that of the alloy steel.Fu et al.[5]compared the penetration abilities of ceramic projectiles and standard steel projectiles,and concluded that the penetration effect of the ceramic projectile on the target is better than that of the steel one.

In this paper,the incendiaryagent and copperclad steeljacket at the head of standard 14.5 mm armor-piercing incendiary projectile was replaced with toughened zirconia ceramics,and it was designed to meet the requirement of ballistic trajectory.The performances of ceramic composite projectile and standard projectile penetrating into ceramic composite target were comparatively studied through experiments.A simulation of penetration process was established by finite-element software LS-DYNA to study the fragmentation mechanisms of the standard projectile and the ceramic composite projectile,and the principles of their penetration into the ceramic composite targets.

2.Penetration test

2.1.Projectile,target configuration and test arrangement

Fig.1 shows the standard 14.5 mm armor-piercing incendiary projectile and 14.5 mm ceramic composite projectile.They areequal in mass,basically the same in shape and con figuration(both are composed of steel core and copper clad steel jacket).The main difference between them is that the incendiary agent and jacket are used at the head of the standard projectile,but s ceramic nose is used in the ceramic composite projectile.The ceramic nose is made through the sintering and processing of toughened zirconia ceramics,which has the features of high strength,high hardness and good fracture toughness.There is a buffer cushion between the ceramic nose and the projectile body.

Fig.2 shows the ceramic composite target used in test,which is composed of an alumina ceramic panel(both sides of the ceramic panel are bonded with fiberglass layers) and a 200 mm×200 mm×15 mm armor steel backplate.

In order to evaluate the penetration performance of the ceramic composite projectile,the above two types of projectiles were tested;in the test,the projectile penetrated the composite target froma side of ceramic panel at an impact velocity of 1000 m/s.Fig.3 shows the test site layout.In Fig.3,the projectile is fired from a ballistic gun,and a net target and an electronic timer are used to measure the impact velocity of projectile.

2.2.Test results

The test results show that the projectiles penetrated straightly into the ceramic composite target without any tilt,as shown in Fig.4,and both the two types of projectiles can destroy the ceramic panels,and the generated ceramic fragments are of no signi ficant difference.Fig.5 shows the fragments of ceramic panel.

When the standard projectile penetrated from ceramic plate to armor plate of the target,it failed to penetrate through the armor plate and left only an impact indentation on it,its steel core was broken as shown in Fig.6,and the fractured steel-core collected in front of the target.However,the ceramic composite projectile successfully penetrated through the armor plate,creating a complete shear plugging,and no residual of the projectile was left.

Fig.7 shows the armor steel backplates hit by the two types of projectiles.The damage range caused by standard projectile is about 47.1 mm×35.3 mm,as shown in Fig.7(a),while the damage caused by ceramiccomposite projectile appearsto be a 26.5 mm×23.9 mm shearing plugging,of which thickness is equal to that of armor steel plate,as shown in Fig.7(b).

3.Numerical simulation of penetration performance

3.1.Numerical model

Fig.1.Test projectiles.

Fig.2.Ceramic composite target.

Fig.3.Test site layout.

Fig.4.The moment of hitting a target.

With the situation of the test,a finite element model was built to show the interaction between the projectile and the composite target.The grids in the target contact area have the same size which is 1 mm,while the grid far away from target interaction area is relatively sparse.The finite element model of projectile and target plate is shown in Fig.8.

Fig.5.Fragments of ceramic panel.

Fig.6.Fragments of standard projectile.

Threekinds of different grid sizes were numericallysimulated to analyze the in fluence of grid size on the penetrationperformance of projectile.The simulated results are shown in Fig.9.The grid sizes have little effect on the penetration velocity(＞200 m/s)of projectile.Therefore,it is desirable that the size of grid in the target contact area is 1 mm.

In the numerical simulation,the ceramic nose and the ceramic panel were simulated using JOHNSON_HOLMQUIST_CERAMICS model which is suitable for brittle material.The material parameters of ceramic nose are listed in Table 1.Ref.[6]is referred for the material parameters of ceramic panel.The steel core,jacket and armor steel backplate were simulated using JOHNSON_COOK model,and Refs.[7,8]are referred for their material parameters. The incendiary agent and the cushion were simulated using PLASTIC_KINEMATIC model.Surface-to-surface erosion contact (CONTACT_ERODING_SURFACE_TO_SURFACE)was used between projectile and targets,and the automatic surface-to-surface contact (CONTACT_AUTOMATIC_SURFACE_TO_SURFACE)wasusedbetween the various components of projectile.

Fig.7.Damage effect on armor steel backplates.

Fig.8.Finite element models.

3.2.Analysis of numerical results

In the numerical simulation,the projectiles penetrated the ceramic target vertically at an initial velocity of 1000 m/s.The jacket and the incendiary agent of standard projectile are almost incapable of penetrating the ceramic plate,the steel core needs to first penetrate the ceramic plate and then penetrate the armor plate.For the ceramic composite projectile,its ceramic nose destroys the ceramic panel prior to its steel core,and the steel core is mainly used to penetrate the steel plate.Fig.10 shows the initialstates of two projectiles penetrating into the armor plate.It can be seen from Fig.10 that the shape of steel core of ceramic composite projectile was not changed,but the steel core head of standard projectile was severely eroded to be blunted.

Fig.9.Effects of grid sizes on penetration velocity of projectile.

Table 1 Material parameters of ceramic nose[9].

Figs.11 and 12 show the mass-time and velocity/accelerationtime histories of the steel cores,respectively.The points in Figs.11 and 12 indicate their conditions at the moment when two steel cores penetrate the surface of armor plate.

It can be seen from Figs.11 and 12 that,when the projectile penetrates the surface of armor steel,the velocities of two steel cores are the same,but the residual mass of standard projectile is about 13%less than that of ceramic composite projectile.The velocity of steel core of standard projectile is reduced to 1000 m/s, and its mass is reduced to 35.2 g.The steel core of ceramic composite projectile is reduced to 564 m/s,and its mass is reduced to 14.5 g.It can be seen that the reduction in velocity and mass of ceramic composite projectile are much smaller than those of standard projectile.

Fig.12 also shows that both the steel cores have the same maximum acceleration,but the maximum acceleration duration of steel core of standard projectile is much longer than that of steel core of ceramic composite projectile.

The damage effects of standard projectile and ceramic composite projectile the target plates are shown in Fig.13.At the end of ion,the standard projectile failed to penetrate through the ceramic composite target,and its damage to the backplate of the armored steel was not serious,as shown in Fig.13(a),while the ceramic composite projectile successfully penetrated through the ceramic composite target,as shown in Fig.13(b).

4.Analyses of penetration performances of two types of projectiles

A large compressive wave is created on the contact surface of ceramic composite target when a projectile impacts the ceramic composite target at a high velocity.After spreading,the compressive waves re flect from the ceramic panel and overlap on it to form a tensile wave.And since the ceramic material compression is not resistant to pull,the ceramic panel will be severely broken under the action of tensile wave.

Fig.10.Comparison of the initial states of two projectiles penetrating into armor plate.

Fig.11.Steel core-mass time curve.

Fig.12.Steel core velocity/acceleration-time curve.

After the standard projectile hit on the ceramic target,its passive armor was broken and the steel core directly acted on the ceramic target.Since the compressive strength and hardness of ceramic materials is much greater than those of the steel,the huge impact stress caused by impact makes the crack happen quickly inside the steel core,leading to the serious crush and break of the steel core,and the penetration ability of projectile is therefore sharply declined so that the damage on armor steel backplane is lighter.

The fracture toughness of zirconia-toughened ceramic nose of ceramic composite projectile is better than that of the alumina ceramic target.The ceramic noses in the process of penetration are mutually eroded with ceramic targets under high-velocity impact along with the occurring of fragmentation and ceramic powder. There is a buffer cushion between the ceramic nose and the metal projectile body.When the stress wave spreads from the ceramic nose to the metal projectile body,the stress wave is attenuated and transmitted through the contact interface between the ceramicnose and the cushion.When the stress wave spreads through the transmitted stress wave,the stress wave is attenuated again. Therefore,the impact of stress wave on the metal projectile body is greatly reduced when the ceramic nose penetrates the ceramic target.The metal projectile remains intact basically after the ceramic targets is destructed by the ceramic nose,sequentially penetrating the armor steel plate so that the plug-type damage occurred.

Fig.13.Damaging effects of projectiles on target plates.

5.Conclusions

1)When the ceramic composite projectile and standard projectile penetrate the ceramic composite targets at the same velocity,the ceramic panels are destroyed by both,while the damage of the armor steel backplate caused by the standard projectile is not serious,the ceramic composite projectile can penetrate through the armor steel backplates.For ceramic composite targets,the ceramic composite projectile is superior to the standard projectile in penetration.

2)The ceramic nose of ceramic composite projectile has a good destructive effect on ceramic target plate,which plays a role in impact crushing and eroding the ceramic target plate,and reduces the consumption of mass and velocity of steel core by the ceramic panel,thus maintaining the penetration ability of the following metal projectile body.

The simulation effects of the steel core of projectile and the crush of ceramic plate are not good enough;related work is still in progress.

[1]Hai-liang Hou,Xi Zhu,Wei LI.Investigation on bullet proof mechanism of ceramic/steel composite armor[J].Acta Armamentarii 2013;34(1):108-14[in Chinese].

[2]Nechitailo NV,Batra RC.Penetration/perforation of aluminum,steel and tungsten plates by ceramic rods[J].Int J Comput Struct 1998;66(5):571-83.

[3]Nechitailo NV.Advanced high-speed ceramic projectiles against hard targets[J]. IEEE Trans Magn 2009;45(1):614-9.

[4]Shou-cang Li,Wei Liu,Zhigang Chen,et al.J Synth Cryst 2009;38:363-5[in Chinese].

[5]Jian-ping Fu,Jin-long Yang,Li-kui Yin,et al.Dynamic properties of Zirconia ceramic bullets under high-speed impact[J].J Chin Ceram Soc 2016;44(2): 346-52[in Chinese].

[6]Anderson CE,Johnson GR,Holmquist TJ.Ballistic experiments and computations of 99.5%AL2O3 ceramic tiles[C].In:Proceeding of fifteenth international symposium on ballistics.Jerusalem,Israel;1995.

[7]Yao-ke Wen,Cheng Xyu,Ai-jun Chen,et al.Numerical simulation of the penetration of bullet on gelatin target[J].Acta Armamentarii 2013;34(1):16[in Chinese].

[8]Lundberg P,Westerling L,Lundberg B.In fluence of scale on the penetration of tungsten rods into steel-backed alumina targets[J].Int J Impact Eng 1996;18(4): 403-16.

[9]Ge Li,Jian-ru Wang,Zhi-gang Chen,et al.Simulation and experimental study of Tc kinetic energy projectile penetrating ceramic composite target[J].Ordnance Material Sci Eng 2015;38(2):100[in Chinese].

11 January 2017

*Corresponding author.National Defense Key Laboratory of Underground Damage Technology,North University of China,3 Xueyuan Road,Taiyuan City 030051,Shanxi,China.

**Corresponding author.

***Corresponding author.

E-mail addresses:yirongcheng58@163.com(R.-c.Yi),303644814@bit.edu.cn (L.-k.Yin),1351362wang@163.com(J.-r.Wang).

Peer review under responsibility of China Ordnance Society.

http://dx.doi.org/10.1016/j.dt.2017.05.009

2214-9147/?2017 Published by Elsevier Ltd.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).

in revised form