Material datasheet · Precipitation-hardening stainless
Stainless Steel 17-4PH
UNS S17400 · Condition A (solution annealed) for machining; aged H900–H1150 for service
Precipitation-hardening stainless. Strength of alloy steel + corrosion resistance of stainless.
Chemical composition
Nominal % by weight.
| Element | % by wt |
|---|---|
| Fe | Bal. |
| Cr | 15.5–17.5 |
| Ni | 3.0–5.0 |
| Cu | 3.0–5.0 |
| Nb+Ta | 0.15–0.45 |
Applicable specifications
AMS / ASTM / MIL.
- AMS 5643
- AMS 5604 (sheet)
- ASTM A564
- ASTM A693
H900: 900°F × 1 hr (max strength). H1025: 1025°F × 4 hr (balanced). H1150: 1150°F × 4 hr (toughest).
Machining guidance
CNC parameters and tooling.
TiAlN-coated carbide
Machine in Condition A, then age. Aging causes <0.1% dimensional change.
Stock & cost
Forms and Q1 2026 pricing.
- Passivate (post-machining)
- PVD coatings
- Black oxide
Typical applications
Where 17-4PH Stainless is the right pick.
- Aerospace landing gear hardware
- Hydraulic valve bodies
- Pump shafts
- Defense ordnance
- Marine
Alternative materials
Substitute or upgrade options.
- 15-5PH (no delta-ferrite)
- 13-8 Mo (premium, transverse properties)
- Custom 465 (higher strength)
True Precision Machining · Buellton, CA
Machine your part in 17-4PH Stainless.
5-axis CNC · ISO 9001 · AS9100 · ITAR · CMMC-compliant · DFARS-compliant supply chain. AS9102 FAI on aerospace.
Technically reviewed by the True Precision Machining engineering team · Last reviewed June 2026
Standards referenced: AMS 5643, AMS 5604 (sheet), ASTM A564, ASTM A693
Keep exploring
Related tools & references
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SFM, RPM, and feed rate for this material.
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Estimate part weight from 17-4PH Stainless stock.
Aerospace specs that call out this alloy.