Stainless Steel 347
Material Data Sheet
347 stainless steel is a columbium/tantalum stabilized austenitic chromium-nickel stainless steel. This material is stabilized against chromium carbide formation by the addition of columbium and tantalum. Since these elements have a stronger affinity for carbon than chromium, columbium-tantalum carbides precipitate within the grains instead of forming at the grain boundaries. 347 should be considered for applications requiring intermittent heating between 800ºF (427ºC) and 1650ºF (899ºC) or for welding under conditions that prevent a post-weld anneal. 347 is non-magnetic.
Chemical Composition
| Element | Content (%) |
|---|---|
| Iron, Fe | 62.83 – 73.64 |
| Chromium, Cr | 17.0 – 20.0 |
| Nickel, Ni | 9.0 – 13.0 |
| Manganese, Mn | 2.0 |
| Silicon, Si | 1.0 |
| Niobium, Nb | 0.320 – 1.0 |
| Carbon, C | 0.04 – 0.10 |
| Phosphorous, P | 0.04 |
| Sulfur, S | 0.03 |
Physical Properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.0 g/cc | 0.289 lb/in³ |
| Melting Point | 1400 – 1425 °C | 2550 – 2600 °F |
Mechanical Properties
| Property | Metric | Imperial |
|---|---|---|
| Hardness, Brinell | 212 | 212 |
| Hardness, Knoop | 235 | 235 |
| Hardness, Rockwell B | 94 | 94 |
| Hardness, Rockwell C | 16 | 16 | Hardness, Vickers | 223 | 223 |
| Tensile Strength, Ultimate | 690 MPa | 100000 psi |
| Tensile Strength, Yield | 450 MPa | 65300 psi |
| Elongation at Break | 40% | 40% |
| Modulus of Elasticity | 195 GPa | 28300 ksi |
| Poisson’s Ratio | 0.27 | 0.27 |
| Charpy Impact | 160 J | 118 ft-lb |
| Izod Impact | 120 – 160 J | 88.5 – 118 ft/lb |
| Shear Modulus | 77 GPa | 11200 ksi |
Applications
Stainless Steel 347 is used in the following application areas:
- Collector rings
- Airplane exhaust stacks
- Annealing box covers
- Jet engine parts expansion joints
- Tubing
- Fasteners
- Flexible metal hose
- Bellows
