Jan 22 2013
Topics Covered
IntroductionChemical CompositionPhysical propertiesMechanical PropertiesThermal PropertiesOther DesignationsFabrication and Heat Treatment Machinability Forming Welding Forging Hot Working Cold Working HardeningApplications
Introduction
Super alloys or high performance alloys consist of a number of elements in different combinations to obtain the desired result. They have good creep and oxidation resistance, and can be strengthened by solid-solution hardening, precipitation hardening, and work hardening. Cobalt-based, nickel-based, and iron-based alloys are three types of super alloys. The cobalt-based super alloys provide good hot corrosion resistance especially in gas turbine areas as they contain high level of chromium. The iron-based alloys are strengthened by intermetallic compound precipitation in fcc matrix. The nickel-based alloys contain solutes such as titanium and/or aluminum.
Ultimet (r) alloy has high strength and wear and corrosion resistance. The following datasheet gives an overview of Ultimet(r) alloy.
Chemical Composition
The chemical composition of Ultimet(r) alloy is outlined in the following table.
| Element |
Content (%) |
| Cobalt, Co |
54 |
| Chromium, Cr |
26 |
| Nickel, Ni |
9 |
| Molybdenum, Mo |
5 |
| Iron, Fe |
3 |
| Tungsten, W |
2 |
| Manganese, Mn |
0.8 |
| Silicon, Si |
0.3 |
| Nitrogen, N |
0.08 |
| Carbon, C |
0.06 |
Physical properties
The physical properties of Ultimet (r) alloy are given in the following table.
| Properties |
Metric |
Imperial |
| Density |
8.47 g/cm³ |
0.306 lb/in³ |
| Melting point |
1399°C |
2550°F |
Mechanical Properties
The following table displays the mechanical properties of mill annealed Ultimet(r) alloy.
| Properties |
Metric |
Imperial |
| Tensile strength |
1020 MPa |
148000 psi |
| Yield strength (@ strain 0.200%) |
545 MPa |
79000 psi |
| Charpy impact |
176 J |
130 ft-lb |
| Elastic modulus (@ 649°C/1200°F) |
180 GPa |
26100 ksi |
| Elongation at break (in 50.8 mm) |
36% |
36% |
| Hardness, Brinell (converted from Rockwell C hardness) |
290 |
290 |
| Hardness, Knoop (converted from Rockwell C hardness) |
311 |
311 |
| Hardness, Rockwell C |
30 |
30 |
| Hardness, Vickers (converted from Rockwell C hardness) |
301 |
301 |
Thermal Properties
The thermal properties of Ultimet(r) alloy are given in the following table.
| Properties |
Metric |
Imperial |
| Thermal expansion co-efficient (@ 26-316°C /78.8-601°F) |
14 µm/m°C |
7.78 µin/in°F |
| Thermal conductivity |
12.3 W/mK |
85.4 BTU in/hr.ft².°F |
Other Designations
Other designations that are equivalent to Ultimet(r) alloy include:
Fabrication and Heat Treatment
Machinability
Ultimet(r) alloy has machining characteristics similar to that of nickel-based alloys.
Forming
Ultimet(r) alloy can be cold formed using conventional methods.
Welding
Ultimet(r) alloy can be welded using all conventional techniques.
Forging
Forging of Ultimet(r) alloy is performed similar to that of nickel-based alloys
Hot Working
Ultimet(r) alloy is hot worked similar to that of nickel-based alloys.
Cold Working
Ultimet(r) alloy can be cold formed in the form of strip or sheet.
Hardening
Ultimet(r) alloy is strengthened and hardened only by cold working.
Applications
Ultimet(r) alloy is used in industrial components such as valves, mixers, nozzles, and slurry pumps.