6-4 ELI

6Al-4V ELI Titanium Sheet

Product Description

Ti 6Al-4V ELI is the extra-low interstitial version of Ti 6Al-4V and its content is arrived at by the careful selection of ingot raw materials. It has been the material of choice for many medical and dental applications due to its excellent biocompatibility. The ELI grade has superior damage tolerance (fracture toughness, fatigue crack growth rate) and better mechanical properties at cryogenic temperatures compared to standard grade Ti 6Al-4V. It is also known as ASTM B348 Grade 23.

Ti 6Al-4V and Ti 6Al-4V ELI are the most widely used titanium alloys and account for more than half of all the titanium sponge used worldwide. Aerospace applications account for 80% of that usage. The remainder is found in defense, marine, medical, chemical, and other industries.
Neither grade of Ti 6Al-4V has corrosion properties quite as good as CP titanium, but both are corrosion resistant in seawater, oxidizing acids, aqueous chlorides, wet chlorine gas, and sodium hypochlorite.
Altering the interstitial levels tends to enhance certain properties; Ti 6Al-4V ELI (Extra Low Interstitials) is a popular alloy where medium strength and good toughness are required. The strength and ductility are similar, but the fracture toughness of the ELI grade is about 25% higher than the standard grade. The ELI grade is usually specified for seawater applications (MIL-T-9047) and for medical use (ASTM F136). A medical grade of Ti 6Al-4V (ASTM F1472) also exists.
Standard: AMS 4907K, AMS-T-9046A, ASTM B265, ASTM F136, BS7252 PART 3, ISO 5832-3, MIL-T-9046, VMI 616-23, AMS 4905, AMS 4907, ASTM F1472.

 Principal Uses  Liquid hydrogen tankage – Principal Uses: Surgical appliances & implants, orthopedic implants, etc.
 Available Forms  Sheet, strip, plate, bar, billet, wire, extrusions, and tubing
 Nominal Composition  0.08% max C, 0.05% max N, 0.015% max H (sheet) ➀ 0.013% max O, 5.5-6.5% AL, 3.5-4.5% V, 0.25% max Fe
 Type Structure  Alpha-Beta
 Mechanical Properties  Guaranteed RT Minimum  Typical Properties at
 -320F  -423F
 Ultimate Tensile Strength, psi  130,000  218,000  263,000
 Yield Strength, 0.2% offset, psi  120,000  202,000  248,000
 El in 2″ (> 0.025″ thick), pct  10 ➁  13.5  6
 Reduction of Area, percent      
 Bend Radius  4.5T ➂ %t ➃    
 Impact, Charpy V, ft-lb, Room Temperature  19    
 Welded Bend Radius  6-10 T    
 Hardness  Rc 30/34    
 Rupture, Stress to Produce in ( ) hr, psi      
 Creep Data, Stress to Produce ( ) percent elongation in ( ) hr, psi      
 Physical Properties  
 Modulus of Elasticity, psi (106) tension  16.5
 Modulus of Elasticity, psi (106) torsion  Approx. 6.10
 Density, lb / cu inch  0.160
 Melting Range, deg F  Approx. 3000F
 Specific Electrical Resistivity micro ohms/cm/sq cm  171 at room temperature
 Specific Heat, Btu/lb/deg F  0.135 at room temperature
 Thermal Conductivity, Btu/hr.ft2-deg F/ft  
 Mean Coefficient of Thermal Expansion per deg F. (10-6)  32 – 212F  5.3
 32 – 600F  5.3
 32 – 1000F  5.3
 32 – 1200F  5.5
 32 – 1500F  5.7
 Oxidation Characteristics in Air    
 Short Time  
 Long Time  
 Remarks on Fabrication  
 Beta Transus  1820±25F
 Cutting  Readily cut with saw or abrasive wheel
 Machinging  Rigid set-up, slow speed, heavy feed, sharp tools, adequate coolant
 Forming  Formable; warm forming useful with solution treated material
 Joining, Welding  Sound ductile welds if protected
 Remarks on Heat Treatment  
 Initial Forging  1800F – 1820F, no higher than 1750F to finish
 Sheet – Strip – Plate Annealing – Bars and Forgings  1300 – 1600F, 15 – 60 min, air cool slower 1300 – 1450F, 1 – 2 hours, air cool or slower
 Solution Treating  Not Applicable
 Aging  Not Applicable
 Stress Relief Annealing←  900 – 1200F, 1 – 4 hr, AC  ←  ←
 Notes and General Remarks  ➀ 0.0125% max H (bar), 0.0100% max H (billet) ➁ 0.020 and below 8%; 10% for plate; determined by configuration of bar and forgings ➂ < 0.070 inch ➃ > 0.070 inch  ←