Nov 20 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
Annealing
Welding
Forging
Forming
Machinability
Hardening
Applications
Introduction
Super alloys or high performance alloys include iron-based, cobalt-based and nickel-based alloys. These alloys can be strengthened by precipitation hardening, solid-solution hardening and work hardening methods. Super alloys can function under high mechanical stress and high temperatures and also in places that require high surface stability. Super alloys are of different shapes and possess good oxidation and creep resistance.
Nitronic 33™ has high yield strength along with ductility and toughness. This nitrogen-strengthened austenitic stainless steel is designed specifically with strong cryogenic properties, low magnetic permeability and high yield strength.
The following datasheet provides an overview of Nitronic 33™.
Chemical Composition
The chemical composition of Nitronic 33™ is outlined in the following table.
|
Element |
Content (%) |
|
Chromium, Cr |
17.00 min.–19.00 max. |
|
Manganese, Mn |
11.50 min.–14.50 max. |
|
Nickel, Ni |
2.25 min.–3.75 max. |
|
Silicon, Si |
0.75 |
|
Nitrogen, N |
0.20 min.–0.40 max. |
|
Phosphorus, P |
0.06 |
|
Sulfur, S |
0.03 |
|
Carbon, C |
0.08 |
Physical Properties
The following table shows the physical properties of Nitronic 33™.
|
Properties |
Metric |
Imperial |
|
Density |
7.775 g/cm3 |
0.2808 lb/in³ |
Mechanical Properties
The mechanical properties of Nitronic 33™ are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
0.689 GPa |
100 ksi |
|
Yield strength |
0.379 GPa |
55 ksi |
|
Elongation at break (in 2 in.) |
40% |
40% |
|
Hardness, Brinell |
241 |
241 |
|
Hardness, Rockwell B |
100 |
100 |
Thermal Properties
The thermal properties of Nitronic 33™ are given in the following table.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@78-200°F/26-93°C) |
16.074 µm/m°C |
8.93 µin/in°F |
Other Designations
Equivalent materials to Nitronic 33™ are provided in the table below.
|
ASTMA240(XM-29) |
ASTMA249(XM-29) |
ASTMA269(XM-29) |
ASTMA479(XM-29) |
|
ASTMA276 |
ASTMA312(XM-29) |
ASTMA412(XM-29) |
ASTMA580(XM-29) |
|
ASTMA688(XM-29) |
ASTMA813(TPXM-29) |
ASTMA814(TPXM-29) |
|
Fabrication and Heat Treatment
Annealing
Nitronic 33™ is soaked at 1038-1121°C (1900-2050°F) and then rapidly quenched in water or air
Welding
Common welding techniques are used for Nitronic 33™ such as submerged arc welding, gas metal arch welding, and gas tungsten arc welding.
Forging
Nitronic 33™ is heated to 1093°C (2000°F) and then soaked to equalize. The alloy is again heated to 1177°C (2150°F) and equalized before being forged.
Forming
Nitronic 33™ can be formed by the commonly used forming methods. For instant annealing, this alloy is heated to 1065°C (1950°F). The stress that is formed due to the high hardening rate is removed by a process annealing method.
Machinability
Nitronic 33™ can be machined by commonly used machining methods, and usage of resulphurized lubricant, positive feeds and slow speeds are recommended for the machining process of this alloy. Breakers or curlers can also be used as the chips might be stringy or tough.
Hardening
Nitronic 33™ can be hardened when cold worked. It cannot be hardened under thermal treatment.
Applications
Nitronic 33™ include the following applications:
-
Tube assemblies
-
Pipes
-
Cable
-
Valves
-
Tanks
-
Containment rings
-
Fans