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Aluminum		2.5 - 3.5
Carbon		0.05 max
Chromium		2.5 - 3.5
Hydrogen 2		0.015 max
Iron		0.25 max
Nitrogen		0.05 max
Oxygen		0.13 max
Remainder Each		0.1 max
Remainder Total		0.4 max
Tin		2.5 - 3.5
Titanium		Balance
Vanadium		14 - 16

Principal Design Features		15-3-3-3 is an age hardenable, metastable-beta alloy used primarily in sheet metal applications due to its excellent strength and cold formability characteristics. It is available from mill producers but is not solidly supported by any of the known national distributors. Beta Transus (F +/- 25) 1400.

Applications		This alloy is currently used primarily for airframe applications although it has also been considered for a variety of aerospace fasteners, tubing and tankage components.

Machinability		As a family, titanium and its alloys have developed a mystique as a nightmare to machine. This is simply not the case. Experienced operators have compared its characteristics to those found in 316 stainless steel. Recommended practice includes high coolant flow(to offset the material's low thermal conductivity), slow speeds and relatively high feed rates. Tooling should be tungsten carbide designations C1-C4 or cobalt type high speed tools.

Forming		This alloy can be hot or cold formed and will exhibit characteristics equivalent to those found in a 1/8 to 1/4 hard austenitic stainless steel. It is strip-producible and highly cold formable.

Welding		Rated as "good" in terms of weldability.

Heat Treatment		Solution treat at 788-816 C(1450-1500 F), 3-30 minutes followed by air cooling.

Forging		Rough forge at 982-1093 C( 1800-2000 F), finish at 816-927 C(1500-1700 F).

Hot Working		Hot forming will reduce both the springback and required forming forces, and will increase the overall ductility of the material.

Cold Working		The cold working characteristics of this alloy are similar to those found in austenitic stainless steels. In multiple forming operations, intermediate stress relieving is recommended to offset the alloy's tendency to work harden. Post-work annealing is recommended to reattain maximum performance characteristics.

Annealing		Stress relieve at 538-649 C(1000-1200 F). For full solution annealing, soak at 1450 F and air cool.

Aging		Age at 538 C(1000 F) for 8 hours, air cool.

Other Physical Props		Beta Transus (F +/- 25) 1400

Physical Data : [top]

Density (lb / cu. in.)	0.172
Modulus of Elasticity Tension	13.5

Form		Sheet
Condition		Solution Annealed & Aged
Temper		70
Tensile Strength		145
Yield Strength		140
Elongation		7