Nov 13 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesThermal PropertiesFabrication and Heat Treatment Machinability Forming Welding Cold Working AnnealingApplications
Introduction
Super alloys are also known as high performance alloys. They contain many elements in a variety of combinations so as to achieve the desired result. These alloys can function under very high temperatures and extreme mechanical stress, and also where high surface stability is required. They have good creep and oxidation resistance.
Strengthening of super alloys is performed by solid-solution hardening, work hardening, and precipitation hardening methods.
Nimonic 101™ has increased chromium content, which provides it with excellent heat corrosion resistance in environments containing sulfur or salt.
The following datasheet will provide more details about Nimonic 101™.
Chemical Composition
The following table shows the chemical composition of Nimonic 101™.
| Element |
Content (%) |
| Chromium, Cr |
24.2 |
| Cobalt, Co |
19.7 |
| Titanium, Ti |
3 |
| Molybdenum, Mo |
1.5 |
| Aluminum, Al |
1.4 |
| Niobium, Nb |
1 |
| Carbon, C |
≤0.1 |
| Zirconium, Zr |
0.05 |
| Boron, B |
0.012 |
Physical Properties
The physical properties of Nimonic 101™ are outlined in the following table.
| Properties |
Metric |
Imperial |
| Density |
7.7-8.03 g/cm³ |
0.278- 0.290 lb/in³ |
| Melting point |
1315°C |
2400°F |
Mechanical Properties
The mechanical properties of Nimonic 101™ are provided below.
| Properties |
Metric |
Imperial |
| Tensile strength (oil quenched, fine grained, tempered at 425°C) |
1158 MPa |
167954 psi |
| Yield strength (oil quenched, fine grained, tempered at 425°C) |
1034 MPa |
149969 psi |
| Elastic modulus |
190-210 GPa |
27557-30457 ksi |
| Poisson’s ratio |
0.27-0.30 |
0.27-0.30 |
| Elongation at break (oil quenched, fine grained, tempered at 425°C) |
15% |
15% |
| Reduction of area |
53% |
53% |
Thermal Properties
The thermal properties of Nimonic 101™ are given below.
| Properties |
Conditions |
| T (ºC) |
Treatment |
| Thermal conductivity |
23.6 W/mK |
100 |
- |
Fabrication and Heat Treatment
Machinability
Traditional machining methods that are used for iron-based alloys can be used for Nimonic 101™. During high speed operations such as grinding, turning, or milling, water-base coolants are preferred. The use of heavy lubricants while drilling, tapping, broaching or boring is recommended. In cases where turning with a continuous cut is performed, carbide tools are suitable.
Forming
Nimonic 101™ has good ductility and can be easily formed using all the conventional methods. Powerful equipment is required.
Welding
Nimonic 101™ can be welded using the traditional welding methods. Some of the commonly used methods are gas-tungsten arc welding, shielded metal-arc welding, gas metal-arc welding and submerged-arc welding. It is recommended that matching alloy filler metal should be used. Before the welding process begins, the surface to be welded should be cleaned and should be free from oil, paint or crayon stains.
Cold Working
Cold working can be performed using standard tooling. To minimize galling and provide a neat finish, soft die materials containing bronze and zinc alloys are recommended. However, the life of the die is short.
Annealing
Nimonic 101™ can be annealed at 1121°C (2050°F) and followed by rapid cooling.
Applications
Nimonic 101™ is mainly used in gas turbine hot section components, e.g. turbine blades, which are required in marine environments or where low grade sulfur-containing fuels are burnt.