Stainless Steel 17-4 PH (UNS S17400)
Stainless Steel 17-4 PH is a chromium-copper precipitation-hardening martensitic stainless steel. It is widely regarded as one of the most versatile "super-steels" available, providing an incredible combination of high strength, high hardness, and excellent corrosion resistance. By utilizing a low-temperature heat treatment, 17-4 PH can reach tensile strengths of up to 180,000 psi, making it significantly stronger than standard austenitic stainless steels like 304 or 316.
At Aries Alloys, we supply 17-4 PH to industries where failure is not an option. Whether it’s for aerospace fasteners or high-pressure pump shafts, our material is selected for its metallurgical stability and its ability to be machined in the annealed state before being hardened to the desired specification.
Key Performance Benefits
- High Strength & Hardness: Capable of reaching massive load-bearing capacities through simple precipitation hardening (aging) treatments.
- Corrosion Excellence: Offers corrosion resistance comparable to Type 304 in most environments, outperforming all other standard hardenable (400-series) stainless steels.
- Low-Temperature Hardening: Can be hardened at temperatures as low as 900° F (482° C), which minimizes scaling and distortion of finished parts.
- Superior Fabricability: Can be easily welded and machined while in the "Solution Treated" (Condition A) state.
- Magnetic Reliability: Naturally magnetic, providing functional utility in specialized sensor and mechanical applications.
Technical Profile & Composition
The Precipitation Hardening (PH) Process:
The defining feature of 17-4 PH is its Copper (3-5%) content. During the aging process, this copper forms microscopic precipitates throughout the metal matrix, which "pins" the crystalline structure and dramatically increases the material's strength and hardness.
Hardening Conditions Supplied by Aries Alloys:
- Condition A (Solution Treated): For maximum formability and machining.
- H900: The highest strength and hardness level.
- H1150: Provides improved ductility and impact strength for high-vibration environments.
- H1150M: The most ductile state for extreme cold-forming applications.
Primary Industrial Use Cases
Aries Alloys is a preferred supplier of 17-4 PH for high-consequence engineering:
- Aerospace & Defense: Structural parts, engine components, landing gear, and high-strength fasteners.
- Oil & Gas: Pump shafts, valve stems, balls, and specialized offshore equipment.
- Chemical Processing: Mixers, high-pressure valves, and equipment handling mildly corrosive slurries.
- Nuclear Industry: High-strength hardware for containment and fuel handling.
- Medical Technology: Surgical instruments and orthopedic components requiring high hardness and sterilization resistance.
Product Availability at Aries Alloys
We maintain a robust inventory of 17-4 PH in accordance with ASTM A564 and AMS 5643:
- Round & Hex Bars: Precision-ground rods for high-speed machining of shafts and bolts.
- Sheets & Plates: Durable flat products for heavy-duty structural components.
- Custom Forgings: Precision-forged rings and blocks for high-pressure industrial service.
- Seamless Tubing: High-strength tubing for hydraulic and chemical transport.