15-5 PH
UNS S15500
Precipitation-hardening martensitic stainless steel designed for high-strength CNC parts, good toughness, dimensional stability and reliable corrosion performance.
A PH stainless steel for strength, precision and stability
15-5 PH - UNS S15500 is a precipitation-hardening martensitic stainless steel, used when a part requires high mechanical strength, good toughness and dimensional stability.
It is an evolution of 17-4 PH developed to improve toughness through finer control of the microstructure. Its combination of chromium, nickel, copper and niobium/tantalum allows high mechanical properties to be achieved after the appropriate heat treatment.
Material identification
What is 15-5 PH?
It is a precipitation-hardening stainless steel based on chromium, nickel, copper and niobium/tantalum, designed for applications where mechanical strength and material reliability are critical.
Unlike conventional austenitic stainless steels, 15-5 PH can adjust its final properties through ageing treatments. This allows the part to be adapted to the required balance between strength, hardness, toughness, ductility and service performance.
High strength
Material suitable for components subjected to high mechanical loads.
Improved toughness
Developed as an evolution of 17-4 PH with greater structural control.
PH treatment
Final properties are adjusted through thermal ageing.
Critical parts
Used in aerospace, valves, shafts, fasteners and technical equipment.
Why it is used in highly demanding components
15-5 PH is selected when the part requires mechanical strength, hardness, dimensional stability, traceability and corrosion resistance suitable for demanding industrial applications.
| Property | Technical advantage |
|---|---|
| High mechanical strength | Suitable for parts subjected to load, pressure, fatigue or high stress. |
| Precipitation hardening | Allows properties to be adjusted through treatments such as H900, H1025 or H1150. |
| Good toughness | Designed to improve behaviour compared with previous PH grades. |
| Good corrosion resistance | Interesting for technical applications requiring high-strength stainless steel. |
| Dimensional stability | Useful in machined parts with tight tolerances and functional requirements. |
| Critical industrial use | Applicable in aerospace, defence, valves, pumps, shafts, fasteners and special equipment. |
A chemistry designed for precipitation hardening
15-5 PH combines chromium, nickel, copper and niobium/tantalum to obtain a precipitation-hardening martensitic structure.
Chromium provides corrosion resistance, nickel supports toughness, copper participates in the hardening mechanism and niobium/tantalum helps control the structure and response to heat treatment.
Typical chemical composition
H conditions to adapt strength and ductility
15-5 PH is usually supplied in solution-treated condition and then aged to reach the mechanical condition specified in the drawing or standard.
Maximum strength
Condition aimed at obtaining high strength and hardness.
Technical balance
Good compromise between strength, ductility and service stability.
Greater toughness
Intermediate condition when reducing hardness and improving behaviour is required.
More ductility
Condition aimed at higher ductility and resistance to certain service environments.
Where 15-5 PH is used
This material is used in sectors where parts require strength, dimensional control, traceability, good toughness and stable behaviour under demanding conditions.
Aerospace
Defence
Valves
Fasteners
Technical shafts
Pumps
Chemical equipment
Nuclear components
CNC machining of 15-5 PH
Machining 15-5 PH requires control of hardness, temperature, surface finish, deformation and dimensional stability.
At AREM-CNC, we manufacture parts in special stainless steels from drawings, physical samples or technical specifications, adapting the process to the material condition, heat treatment, geometry, tolerances and required documentation.
Made-to-drawing production
- Special screws and studs.
- Nuts, washers and technical bushings.
- Shafts, pins and precision components.
- Parts for valves, pumps and pressure equipment.
- Aerospace and industrial fasteners.
- One-off, short-run or medium-run production according to specification.
Controlled production for high-performance parts
CNC manufacturing transforms 15-5 PH into precise, repeatable and traceable components for sectors where strength, geometry and technical documentation are decisive.
Precise geometry
Manufacturing adapted to drawing, sample or technical specification.
High strength
Material suitable for components with high mechanical requirements.
Dimensional control
Verification of dimensions, tolerances and functional requirements.
PH treatment
Possibility to work according to the required H condition or state.
Technical finish
Surfaces adapted to assembly, fit, sealing or mechanical function.
Traceability
Documentation associated with material, batch, process and final control.
Technical documentation for PH steels
In precipitation-hardening materials, traceability allows control of composition, batch, supply condition, heat treatment and final part requirements.
Depending on the project, we can work with material certificates, heat numbers, treatment condition, dimensional control, technical drawings and final documentation associated with manufacturing.
Frequently asked questions about 15-5 PH
What is 15-5 PH stainless steel?
It is a precipitation-hardening martensitic stainless steel, identified as UNS S15500, used for high-strength parts, good toughness and dimensional stability.
What does PH mean?
PH means precipitation hardening. Its mechanical properties are adjusted through ageing heat treatments.
How does it differ from 17-4 PH?
15-5 PH was developed as a variant of 17-4 PH with greater control of the microstructure and improved toughness behaviour.
Can made-to-drawing CNC parts be manufactured in 15-5 PH?
Yes. CNC machining can be used to manufacture screws, nuts, washers, shafts, pins, bushings, fasteners and special made-to-drawing components, provided that the geometry is feasible.
Why is it important to specify the H condition?
Because the strength, hardness, ductility and final behaviour of 15-5 PH depend on the material condition and the specified ageing treatment.
Do you need parts manufactured in 15-5 PH?
Send us your drawing, physical sample or technical specification. We will review material, supply condition, treatment, tolerances, geometry and required documentation to manufacture a reliable solution.