MILITARY APPLICATIONS FOR BETA TITANIUM ALLOYS
John Fanning TIMET Henderson Technical Lab Henderson, NV TITANIUM 2005 Scottsdale, AZ September 25 – 27, 2005
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Two R&D Thrusts for Ti in Military Applications:
Focus of this presentation
1.
Reduced cost, improved availability and consistent ballistic performance for Ti-6Al-4V • Electron Beam Single Melting • Thermomechanical Processing Development
2.
Advanced alloys with improved properties. • Armor • Mortars and Missile Tubes
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Outline • Ballistic Protection – Armor Piercing Projectiles – Ball Projectiles – Sharp Instruments
• Mortar Barrels • Missile Launch Canisters
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Test Method
.30 (7.62mm) AP M2 Projectile TIMET
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Test Method (cont.)
4.6m (15 ft)
15.2m (50 ft)
3.0m (10 ft)
152mm
Line of Fire
Weapon or Barrel
Chronograph 1st Screen
2nd Screen
Target Witness Plate
NOT TO SCALE
Test Range Configuration for Ballistic Limit Testing of Titanium Plates
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Ballistic Test Results 3200 2800
V50, feet/second
2400 2000 1600 1200
TIMETAL 6-4 (Ti-6Al-4V)
800 Linear Fit for TIMETAL 6-4
400 0 0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.9
Plate Thickness, in
V50 Ballistic Limit vs. Titanium Alloy Plate Thickness Results for Ti-6Al-4V Only
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Ballistic Test Results 3200 2800
V50, feet/second
2400 2000 1600 TIMETAL 555 (Ti-5.5Al-5V-5Mo-3Cr-0.12O) STA
1200
TIMETAL 15-3 (Ti-15V-3Cr-3Sn-3Al-0.12O) STA
800
VST3553+Zr (Ti-3Al-5V-3Cr-0.4Zr) STA TIMETAL 6-4 (Ti-6Al-4V)
400 0 0.00
Linear Fit for TIMETAL 6-4
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.9
Plate Thickness, in
V50 Ballistic Limit vs. Titanium Alloy Plate Thickness Results for Ti-6Al-4V and Beta Alloys
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Ballistic Test Results 3200 2800
V50, feet/second
2400 2000 1600 TIMETAL 555 (Ti-5.5Al-5V-5Mo-3Cr-0.12O) STA TIMETAL 15-3 (Ti-15V-3Cr-3Sn-3Al-0.12O) STA TIMETAL LCB (Ti-6.8Mo-4.5Fe-1.5Al) STA VST3553+Zr (Ti-3Al-5V-3Cr-0.4Zr) STA TIMETAL 6-4 (Ti-6Al-4V) Linear Fit for TIMETAL 6-4
1200 800 400 0 0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.9
Plate Thickness, in
V50 Ballistic Limit vs. Titanium Alloy Plate Thickness Results for Ti-6Al-4V and Beta Alloys
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Mass Efficiency of Beta Alloys Compared to Ti-6Al-4V for .30 (7.62mm) AP M2 Projectiles Alloy
Density -3
g cm
-3
lbs in
Mass Efficiency
Ti-6Al-4V
4.46
0.161
1.00
Ti-5.5Al-5V-5Mo-3Cr-0.12O [555] STA
4.65
0.168
0.97
VST3553+0.6Zr STA
4.65
0.168
0.86
Ti-6.8Mo-4.5Fe-1.5Al [LCB] STA
4.79
0.173
0.66
Ti-15V-3Cr-3Sn-3Al-0.12O [15-3] STA
4.79
0.173
0.90
STA = Solution Heat Treated + Aged
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles Consideration of Failure Modes
Ti-6Al-4V defeats AP projectiles by entrapment only (core of projectile is not usually damaged). Although hardenable titanium alloys have relatively low mass efficiencies as monolithic armor, some alloys (such as TIMETAL LCB) have shown an ability to fracture AP projectiles in some test conditions. This might offer benefits in some multilayer systems. TIMET
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles
5mm
Entrapment of .30 (7.62mm) AP M2 Projectile in Ti-6Al-4V Plate
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against AP Projectiles FRONT
BACK Remnant .30 AP M2 Projectile
0.25-in (6.4mm)
0.25-in (6.4mm)
High partial penetration of LCB monolithic plate after testing against .30 (7.62mm) AP M2
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against Ball Projectiles TIMETAL 15-3 plate backed with aramid fabric was tested against 7.62 x 39mm M43 Soviet (7.96g [ 123 gr.]; FMJ, mild steel core) ammunition. Results were better than that of a less titanium-intensive system that consisted of a thin sheet of Ti-6Al-4V backed by a greater thickness of aramid fabric. Note that even though the system areal densities were roughly the same, the titanium-intensive system had a significantly higher V50. The ability of the TIMETAL 15-3 plate to damage the mild steel components of the projectiles potentially provides performance advantages in some systems.
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Ballistic Protection Against Ball Projectiles
6 mm 4.8mm TIMETAL 15-3 plus aramid fabric. Areal Density = 30 kg m-2 (6.2 psf) V50 = 721 m s-1 (2365 fps)
2.0mm TIMETAL 6-4 plus aramid fabric. Areal Density = 28 kg m-2 (5.8 psf) V50 = 484 m s-1 (1579 fps)
Effect of Proportion of Titanium on Performance of Armor Residual Projectiles After Testing Against 7.62x39mm
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Mortar Barrels • Candidate Lightweight Materials: – Aluminum – Titanium – Composites
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Mortar Barrels To reduce the weight of the barrel on the 81mm M253 mortar, a TIMETAL 21S mortar barrel was designed, manufactured and tested by the U.S. Army Titanium was selected instead of aluminum or graphite reinforced epoxy composites based on computational modeling of the thermal and mechanical characteristics of a lightweight mortar tube constructed from each of the candidate materials. In all cases, it was assumed that the interior of the tube would contain a steel liner for direct contact with the projectile. REF:L. Burton, “Analysis of Titanium-Sheathed 81-mm Mortar Barrel”
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 -100
120
UTS TYS Elong
108 96 84 72 60 48
Elongation, %
Strength, MPa
Tensile Properties of TIMETAL 21S Plate at Elevated Temperature (SI)
36 24 12 0 0
100
200
300
400
500
600
700
800
900
1000 1100
Test Temperature, C
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Tensile Properties of TIMETAL 21S Plate at Elevated Temperature (ENG)
180 160 Strength, ksi
120
UTS TYS Elong
108 96
140
84
120
72
100
60
80
48
60
36
40
24
20
12
0
0
-200
0
200
400
600
800
1000
1200
1400
1600
1800
Elongation, %
200
2000
Test Temperature, F
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Mortar Barrels
Prototype TIMETAL 21S Mortar Barrel
REF:L. Burton, “Analysis of Titanium-Sheathed 81-mm Mortar Barrel”
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Concentric Canister Launcher TIMETAL 21S and other titanium alloys were evaluated for a Concentric Canister Launcher (CCL) for the Mk41 Vertical Launch System (VLS) A prototype titanium CCL was manufactured and tested with a hemispherical head made from TIMETAL 21S. Although the results were favorable, titanium has not yet been incorporated in this design concept.
REF: R.S. Rosen, R. W. Lowry and M.E. Kassner, “High Temperature Properties of Alloys Being Considered for Design of a Concentric Canister Launcher”
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Concentric Canister Launcher EXHAUST PRODUCTS FLOW THROUGH ANNULAR SPACE
AUXILIARY VIEW
HEMISPHERICAL HEAD MADE FROM TIMETAL 21S (ON PROTOTYPE) REF: R.S. Rosen, R. W. Lowry and M.E. Kassner, “High Temperature Properties of Alloys Being Considered for Design of a Concentric Canister Launcher”
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Concentric Canister Launcher 4.0 TIMETAL 21S
0.2% Yield Stress, ksi
3.5
TIMETAL 15-3
3.0
Beta C
2.5
Ti-6Al-4V
2.0 1.5 1.0 0.5 0.0 1E-3
10E-3
1E-3
10E-3
2000F
2000F
2400F
2400F
Strain Rate (Top Row) and Test Temperature (Bottom Row)
Effect of test temperature and strain rate on the yield strength at very high temperatures REF: R.S. Rosen, R. W. Lowry and M.E. Kassner, “High Temperature Properties of Alloys Being Considered for Design of a Concentric Canister Launcher” J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
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Concentric Canister Launcher 0.2% Yield Stress, MPa
28 TIMETAL 21S
24
TIMETAL 15-3
20
Beta C
16
Ti-6Al-4V
12 8 4 0 1E-3
10E-3
1E-3
10E-3
1093C
1093C
1316C
1316C
Strain Rate (Top Row) and Test Temperature (Bottom Row)
Effect of test temperature and strain rate on the yield strength at very high temperatures REF: R.S. Rosen, R. W. Lowry and M.E. Kassner, “High Temperature Properties of Alloys Being Considered for Design of a Concentric Canister Launcher” J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
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Summary • Beta titanium alloys have mechanical, physical and ballistic properties potentially of interest in a variety of non-aerospace military applications. As discussed in this paper, observations of interest so far include: • As monolithic armor, the ballistic performance of beta alloys is generally less than that of Ti-6Al-4V. However, the higher strength and hardness of beta alloys may offer advantages in certain types of armor systems for armor piercing projectiles. • TIMETAL 15-3 plate backed with aramid fabric can provide an effective system for defeating ball ammunition. TIMET
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
Summary (cont.)
• The good elevated temperature properties of TIMETAL 21S make it potentially suitable for mortar barrel and missile launch canister applications.
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J. C. Fanning, Military Applications for Beta Ti Alloys ITA 2005
