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).