17-4 Precipitation Hardening
UNS S17400
A chromium-nickel-copper precipitation hardening stainless steel, 17-4 is ideal for applications requiring a combination of high strength, moderate abrasion resistance, and consistent physical properties in environments up to 600 °F (316 °C). Its annealed martensitic structure lends itself to simple, low temperature heat treatments, which precipitate copper-rich phases during heating and cooling. Corrosion resistance (atmospheric and acidic) comparable to 304 and 430 stainless steels. Untempered 17-4 material is typically not recommended for direct use, as it is less ductile than aged material and can result in embrittlement or chloride stress corrosion.
| UTS, ksi | 0.2% YS, ksi | Elong. % in 2” or 4XD | Red. of Area, % | Hardness, Rockwell | Impact Charpy V-Notch, ft-lbs | |
| H 900** | 200 | 185 | 14 | 50 | 44 | 15 |
| H 925 | 190 | 175 | 14 | 54 | 42 | 25 |
| H 1025 | 170 | 165 | 15 | 56 | 38 | 35 |
| H 1075 | 165 | 150 | 16 | 58 | 36 | 40 |
| H 1100 | 150 | 135 | 17 | 58 | 35 | 45 |
| H 1150 | 145 | 125 | 19 | 60 | 33 | 50 |
| HH 1150 | 140 | 120 | 22 | 65 | 31 | 55 |
***For applications requiring greater impact toughness, aging for 4 hours develops typical properties UTS - 196 ksi, 0.2% YS - 181 ksi, Elongation in 2" - 14% , Reduction of Area - 52% , Hardness - Rockwell C 43, and Charpy V-notch impact - 20 foot-pounds
|
Typical Composition (Weight %) |
|
| Carbon (C) | 0.04 |
| Manganese (Mn) | 0.40 |
| Phosphorus (P) | 0.020 |
| Sulfur (S) | 0.005 |
| Silicon (Si) | 0.50 |
| Chromium (Cr) | 15.5 |
| Nickel (Ni) | 4.5 |
| Copper (Cu) | 3.50 |
| Niobium (Nb) | 0.30 |
| Iron (Fe) | Balance |
Specifications:
AMS 5604 - Sheet, Strip, Plate
AMS 5643 - Bars, Forgings, Tubing, Rings
AMS 5825 - Welding Wire
AMS 5827 - Welding Electrodes
AMS 7474 - Bolts
ASTM A 564 / ASME SA 564 - Bars, Wires, Shapes
ASTM A 693 / ASME SA 693 - Sheet, Plate, Strip
ASTM S 705 / ASME SA 705 - Forgings