Alloy 347H
(UNS S34700, S34709)W. Nr. 1.450
| Chemical composition | C | Si | Mn | P | S | Cr | Nb-Ta | Ni | Fe |
|---|---|---|---|---|---|---|---|---|---|
| % Present (Max) | 0.4 – 0.10 | 0.75 | 2.00 | 0.045 | 0.030 | 17.00 – 19.00 | 8x(n+t)-1.00 | 9.00 – 13.00 | Bal |
Alloy 347H (UNS S3409) is the higher carbon (0.04 – 0.10) version of the alloy. It was developed for enhanced creep resistance and for higher strength at temperatures above 1000°F (537°C).
In most instances, the carbon content of the plate enables dual certification. Alloy 347 cannot be hardened by heat treatment, only by cold working. It can be easily welded and processed by standard shop fabrication practices.
Note: Values are in accordance with EN 10088 specifications. Actual mill certs available upon request.