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Advantages of Titanium for Ballistic Applications
John FanningTIMET R&D
Presented at TITANIUM 200821 – 24 September 2008
Las Vegas, NV
Review of Advantages of Titanium
Photo Courtesy of BAE Photo Courtesy of BAE
Photo Courtesy of BAE
Photo Courtesy of U.S. Army
High ballistic mass efficiencyWeight savings of 15-45%
Extremely corrosion resistantLasts 50+ years in seawater with no
corrosion
Good Multihit ballistic capabilityTypically exhibits full protection within one shot diameter
High strength-to-weight ratioAlmost half the density of
steel
Lower cost than PMCs or ceramics
Can be fabricated in existing facilitiesMajor armor manufacturers have found little difference once they got used to titanium.
Compatible with PMCsNo galvanic reaction.Similar coefficient of thermal expansion.
No Environmental ProblemsNo painting or coatings required; non-toxic; fully biocompatible; no hazardous debris after a hit.
Non-MagneticDoes not require de-magnetization; does not interfere with navigational equipment; reduces magnetic signature of vehicle.
Example Modern Application
Forged hatch for BFV[after ballistic testing]
Ballistic Properties
Ballistic Properties
Ballistic Properties
Purposes of Ongoing Ballistic Testing:
● Provide technical information to support applications
● Ensure that the specified processing has a robust capability to meet expected performance levels.
● Identify new alloys that may have improved performance.
TIMET Ballistic Evaluations
0
10
20
30
40
50
60
70
80
90
100
860 865 870 875 880 885 890 895 900 905 910Impact Velocity, m s-1
Prob
abilit
y of
Pen
etra
tion,
%
Complete Penetration (CP)
Partial Penetration (PP)
40mm 6-4 Plate vs.14.5mm B32 API
Example Calculation:V50 = Average of High PP and Low CP
= (881+867+875+905+893+888) / 4= 885 m s-1
Probability of Penetration vs. Impact Velocity
NOT TO SCALE
TargetWeaponor Barrel
1st Screen
WitnessPlate
2nd Screen
Line of Fire
Chronograph
Test Range Configuration for Ballistic Limit Testing
Incipient Back Spall Formation (Ductile Tearing)
Impact CraterResidual Projectile
Separation in to Layers (Adiabatic Shear)
Adiabatic Shear
Back Bulge (with initiation of cracking)
10 mm0.4 in
Example Partial Penetration (cross sectional view)
200400600800
10001200
12 16 20 24 28 32 36 40 44 48 52 56 60Plate Thickness, mm
V50
Balli
stic
Lim
it, m
s-1
TIMETAL 6-4Linear Fit
300
400
500
600
700
800
900
1000
1100
12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46
V50
Balli
stic
Lim
it, m
s-1
TIMETAL 6-4TIMETAL 62SForeign Armor ComponentTIMETAL 550Linear Fit - Alpha-Beta Alloys
200300400500600700800900
10001100
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
V50
Balli
stic
Lim
it, m
s-1 TIMETAL 6-4
TIMETAL 62STIMETAL 62S+BLinear Fit - Alpha-Beta Alloys
.30 AP M2
.50 AP M2
14.5mm API B32
V50 test against homologous threats
.30 AP M27.62 mm
10.8 g
.50 AP M212. 7 mm
53.8 g
14.5 mm B32 API14.5 mm
61.6 g
Designation:Nominal Diameter:
Nominal Mass:
15 mm
Characterization of Ti-6-4 Plate vs. AP Projectiles
Ref [1]
Characterization of Ti-6-4 Plate vs. AP Projectiles(cont.)
200400600800
10001200
12 16 20 24 28 32 36 40 44 48 52 56 60Plate Thickness, mm
V50
Balli
stic
Lim
it, m
s-1
TIMETAL 6-4Linear Fit
300
400
500
600
700
800
900
1000
1100
12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46
V50
Balli
stic
Lim
it, m
s-1
TIMETAL 6-4TIMETAL 62SForeign Armor ComponentTIMETAL 550Linear Fit - Alpha-Beta Alloys
200300400500600700800900
10001100
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
V50
Balli
stic
Lim
it, m
s-1 TIMETAL 6-4
TIMETAL 62STIMETAL 62S+BLinear Fit - Alpha-Beta Alloys
.30 AP M2
.50 AP M2
14.5mm API B32
V50 test against homologous threats to determine overall trend.
0
200
400
600
800
1000
1200
1400
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
Plate Thickness to Projectile Diameter Ratio (t/d)
V50
Ballis
tic L
imit,
m/s
Caliber .30 (7.62mm) AP M2Caliber .50 (12.7mm) AP M214.5mm API B3220mm M602 Linear Regression
AP Projectiles
Ref [1]
Ballistic Mass Efficiency of Ti-6-4
Areal Density vs V50 Ballistic Limit for .50 Cal. AP M2Aluminum alloys compared to Ti-6Al-4V
1000
1400
1800
2200
2600
3000
3400
3800
10 14 18 22 26 30 34 38 42 46 50 54
Areal Density, lb ft-2
V50
, ft s
ec-1
Muzzle VelocityTi-6Al-4V [1]Medium Strength Aluminum 5083 [2]High Strength Aluminum (7039, 2519 & 5059) [2,3]
REFERENCES:[1] J.C. Fanning, “Ballistic Evaluation of Ti-6-4 Plate for Protection Against AP Projectiles”, TITAMIUM ’99, 1999[2] G.H. Nickodemus et al., “Aluminum Alloy Advances for Ground Vehicles”, AM&P, 2002
Ti-6-4
Aluminum Alloys
Ref [2,3]
Ballistic Mass Efficiency of Ti-6-4Comparison of Penetration of
Metallic Armor vs. DU Rods (length = 77mm, l/d=10) at 0o Obliquity
3200
3400
3600
3800
4000
4200
4400
4600
4800
5000
5200
5400
5600
5800
6000
20 40 60 80 100 120 140 160Areal Density, lbs ft-2
Striki
ng V
eloc
ity (p
enet
ratio
n) f
t/sec
TIMETAL 6-4RHA Steel
Ref: M.S. Burkins, US Army Research Lab Ref [4]
Ballistic Mass Efficiency of Ti-6-4
Areal Density vs V50 Ballistic Limit for 20mm FSPAluminum and RHA Steel Compared to Ti-6Al-4V
1000
2000
3000
4000
5000
6000
0 5 10 15 20 25 30 35 40
Areal Density, lb ft-2
V50
, ft s
ec-1 Velocity of HE Frag (typical)
Ti-6Al-4V [1]Aluminum 5083 [2]RHA Steel
Ref [2,3]
Comparison of Ballistic Mass Efficiencies
MaterialAP FSP KE
Rolled Homogenous Steel (RHA) 1.0 1.0 1.0
Aluminum (5083, 7039) 0.9 1.2
Ti-6-4 1.2 1.2 - 1.4 >1.4
Aramid Fiber (Kevlar, Twaron) 1.4
Ceramic + Aramid Fiber > 2.0
Ceramic + Metal > 2.0
High Hardness Steel (HHS) 1.3
AP = Armor Piercing; FSP = Fragment Simulating Projectiles, KE = Kinetic Energy Penetrator
Information Derived from a Variety of Sources
Ballistic Mass Efficiency
Ballistic Mass Efficiency = Areal Density of RHA / Areal Density of Ti-6-4
Alloy and Cost Considerations
Cost and Availability Improvements
Electron Beam Single Melting [EBSM]
Hearth
Electron Beams
Ingot Bottom(Dovetail)
Feed
SprayShield
Dip samples taken from molten pool
Mold (other shapes are rectangular or double strand round)
1 m
1 m
Ref [5]
Implementation of EBSM
● First large scale production use of EBSM▪ Titanium (MIL-DTL-46077, class 2)▪ Plate form (E-beam melt process)▪ Turret structural components▪ Material properties have been
excellent▪ Thickness range of 2.0” – 3.0”
REFERNCE: W. Herman, ITA, 2005
Ref [6]
Implementation of EBSM (cont.)
REFERENCE: W. Herman, ITA, 2005
Gun PodWelded titanium armor plateEBSM MIL-A-46077Used as stand alone armor and as part
of more complex recipes
Turret SideFirst use of a ring rolled Ti forging as an
armor material ring rolled materialForms the base structure for the turret
Ref [6]
Development of Titanium Products
Ring for turret armor [after ballistic testing]
MGS in service
In the current environment, the time between development and service has been significantly shortened.
Performance of Titanium in Service
● Most equipment sees action immediately.
● No degradation of capability in operational environments.
● Titanium has consistently provided the expected level of protection.
● Titanium has a key role in saving lives and the successful completion of missions.
The above was presented at ITA 2007, but after another year of combat it is still valid!
Photo Courtesy of BAE
References
1. J.C. Fanning, “Ballistic Evaluation of TIMETAL 6-4 Plate for Protection Against Armor Piercing Projectiles” (Titanium 99 Science and Technology, I.V. Gorynin and S.S. Ushkov, eds., St. Petersburg, Russia, June 1999), 1171-1178.
2. D. Showalter, B. Placzankis, and M. Burkins: Ballistic Performance Testing of Aluminum Alloy 5059-H131 and 5059-H136 for Armor Applications, Army Research Laboratory ARL-TR-4427 (May 2008).
3. G. Nickodemus, L. Kramer, J. Pickens, M. Burkins: “Aluminum Alloy Advances for Ground Vehicles”, Advanced Materials and Processes, ASM (February 2002).
4. M. Burkins, J. Paige, J, Hansen: A Ballistic Evaluation or Ti-6Al-4V vs. Long Rod Penetrators, Army Research Laboratory ARL-TR-1146 (July 1996).
5. M. Burkins, M. Wells, J. Fanning, and B. Roopchand: The Mechanical and Ballistic Properties of an Electron Beam Single Melt of Ti-6Al-4V Plate, Army Research Laboratory ARL-MR-515 (May 2001).
6. W. Herman: “Titanium in Combat Vehicles”, TITANIUM 2005, ITA (2005).