Jul 18 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Fabrication and Heat Treatment
Machinability
Forming
Welding
Heat Treatment
Forging
Hot Working
Cold Working
Other Designations
Applications
Introduction
Sanicro 70 is an austenitic nickel-chromium-iron alloy that is characterized by excellent resistance to nitrogen absorption and carburization, and good structural stability at high temperatures. It also has good resistance to stress corrosion cracking.
The following section will provide a brief description of Sanicro 70 alloy.
Chemical Composition
The chemical composition of Sanicro 70 alloy is outlined in the following table.
|
Element |
Content (%) |
|
Nickel, Ni |
72.5 |
|
Chromium, Cr |
16.5 |
|
Iron, Fe |
≤≤10 |
|
Manganese, Mn |
0.8 |
|
Copper, Cu |
≤0.50 |
|
Carbon, C |
≤0.50 |
|
Silicon, Si |
0.4 |
|
Sulfur, S |
≤0.015 |
|
Phosphorous, P |
≤0.015 |
Physical Properties
The following table shows the physical properties of Sanicro 70 alloy.
|
Properties |
Metric |
Imperial |
|
Density |
8.40 g/cm3 |
0.303 lb/in3 |
|
Melting point |
1399°C |
2550°F |
Mechanical Properties
The mechanical properties of Sanciro 70 alloy are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
≥560 MPa |
≥81200 psi |
|
Yield strength |
≥245 MPa |
≥35500 psi |
|
Elongation at break |
≥35% |
≥35% |
|
Vickers hardness |
160 |
160 |
Thermal Properties
The thermal properties of Sanicro 70 alloy are given in the following table.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@30-100°C/86-212°F) |
13.5 µm/m°C |
7.5 µin/in°F |
|
Thermal conductivity (@20°C/68°F) |
13 W/mK |
90.2 BTU.in/hrft².°F |
Fabrication and Heat Treatment
Machinability
Conventional machining techniques that are used for machining iron-based alloys can be used.
Forming
Sanicro 70 alloy has excellent ductility, and can be readily formed by all conventional techniques.
Welding
The alloy can be welded using commonly used welding techniques such as gas-tungsten arc welding, shielded metal-arc welding, gas metal-arc welding and submerged-arc welding.
Heat Treatment
Sanicro 70 alloy can be heat treated at 1010°C (1850°F) for 15 min and then air cooled.
Forging
The alloy can be forged in the temperature range of 1038 to 1232°C (1900 to 2250°F).
Hot Working
The alloy can be hot worked in the temperature range of 871 to 1232°C (1600 to 2250°F).
Cold Working
Cold working may be performed using standard tooling.
Other Designations
Other designations that are equivalent to Sanicro 70 alloy include the following:
|
AMS 5540 |
ASTM B167 |
MIL N-23228 |
|
AMS 5580 |
ASTM B168 |
MIL N-23229 |
|
AMS 5665 |
ASTM B516 |
MIL N-6710 |
|
AMS 5687 |
ASTM B517 |
MIL T-23227 |
|
ASTM B163 |
ASTM B564 |
QQ W390 |
|
ASTM B166 |
DIN 2.4816 |
|
Applications
The following are the list of applications of Sanicro 70 alloy:
-
Heaters
-
Gas turbine components
-
Chemical process equipment
-
Fixtures
-
Heat exchangers