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Precipitation-hardening (PH) Stainless Steel

Precipitation-hardening (PH) stainless steels can be hardened by low temperature heat treatments. Many of these alloys have been developed and patented by  with a proprietary designation as a trademark.


These are  17-4PH (Grade UNS S17400),  15-5PH (Grade UNS S15500),  PH 13-8Mo (Grade UNS S13800),  17-7PH (Grade UNS S17700) and  PH 15-7Mo (Grade UNS S15700).

PH stainless steels offer varied and unique combinations of high strength and hardness, excellent corrosion resistance, good fabricating characteristics and ease of hardening by heat treatment. They offer designers outstanding opportunities to meet specific requirements efficiently and economically in applications for the aerospace, chemical processing, automotive, food processing, pulp and paper, textile and petrochemical industries.

15-5 PH (UNS S15500)

  15-5 PH VAC CE Stainless Steel offers a unique combination of high strength and hardness, excellent corrosion resistance plus excellent transverse toughness and good forgeability.

15-5 PH Stainless is widely used in applications requiring high strength and toughness in all directions. Typical applications include forgings, pump and valve parts for high-pressure systems requiring excellent corrosion resistance, aircraft components and transversely loaded plate applications.


17-4 PH (UNS 17400)

17-4PH is the most widely used of all precipitation-hardening stainless steel. Its combination of high strength and hardness, excellent corrosion resistance and easy heat treatment gives designers an opportunity to add reliability to their product and at the same time, simplify fabrication and reduce costs.

The unique combination of properties provided by our 17-4PH stainless steel makes it the “workhorse” of the precipitation hardening stainless steels.

Applications include pump shafts, valve stems, balls, gates, bushings and trim mixing screws, fasteners, couplings, rocket hold-downs, wear rings, rollers, hydraulic actuators and screws.

Industries: Aerospace, Chemical, Petrochemical, food processing, paper and general metalworking.


17-7 PH (UNS S17700)

17-7 PH stainless steel provides high strength and hardness, excellent fatigue properties, good corrosion resistance and minimum distortion upon heat treatment. It is easily formed in the annealed condition, then hardened to high strength levels by simple heat treatment.

17-7 PH stainless steel sheet and strip is widely used for application requiring good corrosion resistance with high strength. With excellent spring properties at temperatures up to 600 F, and good corrosion resistance, it is used for a wide variety of springs.


PH 13-8 MO (UNS S13800)

PH 13-8 Mo stainless steel provides an outstanding combination of excellent toughness and good transverse mechanical properties in addition to the highly strength of a precipitation hardening stainless steel. These properties make our PH 13-8 Mo Stainless ideal for large sections where notch toughness, high strength and stress corrosion resistance are especially important.

PH 13-8 Mo stainless is produced by vacuum induction melting plus consumable electrode vacuum arc re-melting. This melting process is used to control chemical composition within narrow limits and assure optimum solidification conditions. PH 13-8 Mo stainless steel is ideal for high performance applications requiring high strength coupled with excellent corrosion and stress corrosion resistance.

Applications for this high-performance alloy include forgings, cold-headed and machined fasteners, aircraft parts, nuclear reactor components, landing gear parts, pins and lock-washers, high performance shafting and petrochemical applications requiring stress corrosion resistance combined with high strength.


PH 15-7 MO (UNS S15700)

PH 15-7 Mo is a semi-austenitic precipitation-hardening stainless steel that provides high strength and hardness, good corrosion resistance, excellent strengths at elevated temperatures  and minimum distortion on heat treatment. It is easily formed in the annealed condition and develops attractive properties by simple heat treatments.

PH 15-7 Mo stainless steel is ideal for applications such as retaining rings, springs, diaphragms, aircraft bulkheads, welded and brazed honeycomb paneling and other aircraft components requiring high strengths at elevated temperatures.



Sempurna's (PH) Stainless Steels

> PH 15-7 MO (UNS S15700)

> PH 13-8 MO (UNS S13800)

> 17-7 PH (UNS S17700)

> 17-4 PH (UNS 17400)

> 15-5 PH (UNS S15500)


Sempurna's Contact Info

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