Stainless Steel Grade 347 | UNS# S34700 is a stabilized austenitic stainless steel that is very similar to grade/alloy 304 with the inclusion of columbium and tantalum. To avoid chromium carbide precipitation, columbium is used to stabilize. Because of these attributes, type 347 is typically used for exhaust stacks in airplanes, jet engine parts, various expansion joints, fasteners, tubing, metal hosing, and similar applications. Grade 347 is also an ideal material for high temperature service due to its good mechanical properties and excellent resistance to intergranular corrosion when exposed to temperatures in the chromium carbide precipitation range of 800° to 1500°F.
Stainless Steel Grade 347 Specifications:
Stainless Steel Type 347 product forms offered at all Titanium Industries’ locations:
Stainless Steel Grade 347 Applications:
- Jet and Rocket Engines
- High Temp Expansion Joints
- Exhaust Manifolds
- Chemical Production Equipment
- Aircraft Collector Rings
- Valves
DISCLAIMER: Alloy data sheets are for reference only, not for design purposes.
| Chemical Composition | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Fe 68.0% | Cr 17.0% | Mn | C 0.080% | Si | |||||
| Ni 11.0% | S | Nb+Ta 0.80% | P | ||||||
| PHYSICAL PROPERTIES | ||||||
|---|---|---|---|---|---|---|
| Density | Electrical conductivity (% IACS) | Thermal conductivity (BTU-in/hr-ft²-°F) | Specific heat capacity | Thermal expansion (1/°F) | Melting Point (°F) | |
| 0.289 | 2.36 | 113 | 0.12 | 0.00000961 | 2600 | |
| Mechanical Properties | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Property | Minimum | Maximum | |||||||
| Yield Strength Range (Rp0.2 Offset) (ksi) | 30 | 65.3 | |||||||
| Tensile Strength Range (Rm) (ksi) | 75 | 100 | |||||||
| Elongation (AL=5 x Ø) | 40.0% | 45.0% | |||||||
| Brinell Hardness (H) | 187 | 230 | |||||||
| Modulus of Elasticity (ksi) (E): 28300 | |||||||||
| Machineability General Index: 36% | |||||||||
T.I. Approvals:
Plus a wide range of approvals from most leading OEM’s across Aerospace, Medical, Industrial, and Oil and Gas markets.