Jul 5 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
Machinability
Forming
Welding
Annealing
Forging
Hot Working
Cold Working
Aging
Applications
Introduction
Titanium alloys are divided into alpha alloys, near-alpha alloys, alpha and beta alloys, and beta alloys. Grade Ti 15V 3Cr 3Al 3Sn alloy is a beta alloy that can be strip-rolled and heat-treated. It is highly formable, and has good room temperature bending properties. Solution treatment of this alloy enhances its strength.
The following sections will discuss in detail about grade Ti 15V 3Cr 3Al 3Sn alloy.
Chemical Composition
The chemical composition of grade Ti 15V 3Cr 3Al 3Sn alloy is outlined in the following table.
|
Element |
Content (%) |
|
Titanium, Ti |
76 |
|
Vanadium, V |
15 |
|
Aluminum, Al |
3 |
|
Tin, Sn |
3 |
|
Chromium, Cr |
3 |
Physical Properties
The physical properties of grade Ti 15V 3Cr 3Al 3Sn alloy are tabulated below.
|
Properties |
Metric |
Imperial |
|
Density |
4.76 g/cm3 |
0.172 lb/in3 |
Mechanical Properties
The following table shows mechanical properties of grade Ti 15V 3Cr 3Al 3Sn alloy.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
790 MPa |
115000 psi |
|
Yield strength |
770 MPa |
112000 psi |
|
Poisson’s ratio |
0.33 |
0.33 |
|
Elastic modulus |
82.0 GPa |
11900 ksi |
|
Shear modulus |
30.8 GPa |
4470 ksi |
|
Elongation at break |
22% |
22% |
|
Hardness, Rockwell B |
95 |
95 |
Thermal Properties
The thermal properties of grade Ti 15V 3Cr 3Al 3Sn are tabulated below.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@20-100°C/68-212°F) |
8.50 µm/m°C |
4.72 µin/in°F |
|
Thermal conductivity |
8.08 W/mK |
56.1 BTU in/hr.ft².°F |
Other Designations
Equivalent material to grade Ti 15V 3Cr 3Al 3Sn alloy is AMS 4914.
Fabrication and Heat Treatment
Machinability
Grade Ti 15V 3Cr 3Al 3Sn alloy is hard to machine but can be successfully done using slow speeds, high coolant flow, and high feed rates. Tooling should be performed using tungsten carbide designations C1-C4 or cobalt type high speed tools.
Forming
Grade Ti 15V 3Cr 3Al 3Sn alloy can be hot or cold formed. Cold forming is easy to perform. It is strip-producible.
Welding
Weldability of grade Ti 15V 3Cr 3Al 3Sn alloy is rated as good.
Annealing
Full annealing of this material can be performed by soaking at 792°C (1450°F) and then air cooled. The material can be stress relieved at 538-649°C (1000-1200°F).
Forging
Rough forging can be performed at 982-1093°C (1800-2000°F) and completed at 816-927°C (1500-1700°F).
Hot Working
Hot working enhances the overall ductility of the material.
Cold Working
Cold working features of this material is same as that of a moderately tempered austenitic stainless steel. Post-work annealing is recommended to re-attain favorable performance properties.
Aging
Grade Ti 15V 3Cr 3Al 3Sn alloy can be aged at 538°C (1000°F) for 8 h and air cooled.
Applications
Grade Ti 15V 3Cr 3Al 3Sn alloy was primarily developed for airframe applications.
The other application areas include:
-
Aerospace fasteners
-
Tubing and tankage components
-
Flat-rolled products
-
Foil, plate, castings and forgings.