Grade 4 Technical Data

Principal Uses

 Airframe, chemical, marine, and similar applications

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 0.030% max Fe, 0.40 max O

Type Structure

 Alpha

Mechanical Properties

 Guaranteed RT Minimum Typical Strength (%RT) & Ductibility
200F 400F 600F 800F 1000F
Ultimate Tensile Strength, psi 80,000 ➁ ➂ 80 57 46 36 28
Yield Strength, 0.2% offset, psi 70,000 ➁ ➃ 76 46 30 26 20
El in 2" (> 0.025" thick), pct 15 ➁   42 38 23 28
Reduction of Area, percent 35 ➄   65 79 80 76
Bend Radius 2T ➅ 2.5T ➆          
Impact, Charpy V, ft-lb, Room Temperature 11-15          
Welded Bend Radius Approx. 3-4 T          
Hardness Brinell 265 ➄          
Rupture, Stress to Produce in ( ) hr, psi 225 hr
65,000		       430 hr
17,000		  
Creep Data, Stress to Produce ( ) percent elongation in ( ) hr, psi          

Physical Properties

  
Modulus of Elasticity, psi (106) tension 15.1
Modulus of Elasticity, psi (106) torsion Approx. 6.5
Density, lb / cu inch 0.164
Melting Range, deg F 3020±18F
Specific Electrical Resistivity
micro ohms/cm/sq cm		 60
Specific Heat, Btu/lb/deg F 0.129
Thermal Conductivity, Btu/hr.ft2-deg F/ft Approx. 9.8 at room temperature
Mean Coefficient of
Thermal Expansion
per deg F. (10-6)		 32 - 212F 4.8
32 - 600F 5.1
32 - 1000F 5.4
32 - 1200F 5.6
32 - 1500F 5.6
Oxidation Characteristics
in Air		   400F 600F 800F 1000F
Short Time Good Good Good Moderate
Long Time Good Good Slight Moderate

Remarks on Fabrication

  
Beta Transus 1740±25F
Cutting Readily cut with saw or abrasive wheel
Machinging Rigid set-up, slow speed, heavy feed, sharp tools, adequate coolant
Forming Readily formable at room temperature. Complex shapes require heat
Joining, Welding Completely weldable; fusion welding requires protection

Remarks on Heat Treatment

  
Initial Forging 1715F rough breakdown, finish 1550F
Sheet - Strip - Plate
Annealing - Bars and Forgings		 1200 - 1500F, 15 - 120 min, air cool slower
1200 - 1450F, 1 - 2 hours, air cool or slower
Solution Treating Not Applicable
Aging Not Applicable
Stress Relief Annealing 900 - 1000F, 45 min

Notes and General Remarks

 Highest strength commercially pure sheet grade. ➀ 0.0125% max H (bar), 0.0100% max H (billet) ➁ Sheet ➂ Bar: 70,000 ➃ Bar: 60,000 ➄ Bar ➅ < 0.070 inch thick ➆ > 0.070 inch thick