Stainless Steel 15-5 PH · precip hard
Stainless Steel 15-5 PH-H900
Properties of the H900 condition, compared with the other 15-5 PH tempers.
Choose for maximum strength and hardness — aerospace fittings, shafts, valve parts; least tough and most SCC-sensitive age.
What is 15-5 PH-H900?
15-5 PH-H900 is 15-5 PH in the H900 condition — choose for maximum strength and hardness — aerospace fittings, shafts, valve parts; least tough and most SCC-sensitive age. 15-5 PH-H900 has a yield strength of 1,275 MPa (185 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 99% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi). 15-5 PH-H900 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F). Condition A is the default condition FabDigit quotes; H900 is available on request or by drawing note.
Advantages
- High strength — 1,275 MPa (185 ksi), better than 99% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
Limitations
- Limited ductility — 12%, worse than 95% of stainless steel grades
- Limited formability — 10/100, worse than 95% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Low fracture toughness — 70 MPa·√m (63.7 ksi·√in), worse than 87% of stainless steel grades
- Needs corrosion protection — 52/100, worse than 77% of stainless steel grades
15-5 PH-H900 properties
Typical room-temperature values for 15-5 PH-H900 — 20 properties are specific to this condition; the rest are grade-level values shared by every 15-5 PH temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
15-5 PH-H900 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
15-5 PH-H900 has a yield strength of 1,275 MPa (185 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 99% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
15-5 PH-H900 is rated for continuous service to 300°C (572 °F). It conducts heat at 17.9 W/m·K (10.3 BTU/hr·ft·°F), better than 73% of stainless steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
15-5 PH-H900 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (52/100), worse than 77% of stainless steel grades.
Sustainability4
Producing a kilogram of 15-5 PH-H900 takes about 55 MJ of energy and emits 5.5 kg of CO₂ — less than 51% of stainless steel grades. Typical recycled content is 35%.
Manufacturability7
15-5 PH-H900's machinability is poor (28/100, worse than 80% of stainless steel grades); weldability very good (70/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 15-5 PH tempers and conditions
15-5 PH is also supplied in 12 other conditions. The full side-by-side table is on the 15-5 PH overview.
- Condition ADefaultStandard mill-supplied condition: soft-martensitic, machinable and formable, then age-hardened by the user.795 MPa yield · 33 HRC
- H900Choose for maximum strength and hardness — aerospace fittings, shafts, valve parts; least tough and most SCC-sensitive age.1,275 MPa yield · 44 HRC
- H925Small strength give-back from H900 for slightly better toughness and SCC resistance.1,160 MPa yield · 42 HRC
- H1025Balanced strength/toughness age widely used for aerospace and oilfield components.1,070 MPa yield · 39 HRC
- H1075Moderate strength with good ductility and improved chloride SCC resistance.1,000 MPa yield · 36 HRC
- H1100Softer age used when notch toughness and dimensional stability matter more than strength.900 MPa yield · 34 HRC
- H1150Best toughness, ductility and SCC resistance of the single-age conditions; choose for subsea and impact-loaded parts.800 MPa yield · 32 HRC
- H1150DDouble 1150 age for improved toughness and SCC/H2S resistance at moderate strength (oil & gas practice).690 MPa yield · 29 HRC
- H1150MMaximum toughness/ductility variant for cryogenic and high-impact service; lowest strength of the aged conditions.585 MPa yield · 26 HRC
Working with 15-5 PH-H900
Is 15-5 PH easy to machine?
Machine in Condition A or H1150 with rigid setups, sharp positive-rake carbide, heavy feeds and flood coolant; avoid dwelling — the alloy work-hardens, and H900 material cuts at roughly 30 % of AISI 1212.
Can 15-5 PH be welded?
Readily GTAW/GMAW/EB welded without preheat using 15-5 PH or 17-4 PH filler; re-solution treat and age (or at minimum re-age) after welding to restore properties in the HAZ.
Can 15-5 PH be formed, bent or molded?
Cold form only in Condition A and expect high springback and forces; hot work at 1150–1200 °C and never finish below ~925 °C, followed by full solution treatment.
What surface finishes work on 15-5 PH?
Takes a fine mechanical polish thanks to low inclusion content; passivate per AMS 2700/ASTM A967 after machining, and avoid electroplating in H900 unless baked for hydrogen embrittlement relief.
15-5 PH chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CASTM A564 Type XM-12 | ≤ 0.07 | 0.04 |
| Mn | ≤ 1 | 0.5 |
| Si | ≤ 1 | 0.4 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 14 – 15.5 | 15 |
| Ni | 3.5 – 5.5 | 4.5 |
| Cu | 2.5 – 4.5 | 3.5 |
| Nb+Tacolumbium + tantalum, precipitation stabiliser | 0.15 – 0.45 | 0.3 |
| Fe | balance | — |
15-5 PH-H900 — frequently asked
What is 15-5 PH-H900 used for?
15-5 PH-H900 is typically used for aerospace valve bodies, gears and shafts, landing gear and structural fittings, aerospace fasteners, injection mould inserts and pump and compressor components. In short: versatile high-strength PH.
What is the yield strength of 15-5 PH-H900?
15-5 PH-H900 has a typical yield strength of 1,275 MPa (185 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 99% of stainless steel grades. Strength varies by condition: see the 13 listed tempers.
Is 15-5 PH-H900 easy to machine?
Not especially — machinability is rated poor (28/100, worse than 80% of stainless steel grades). Machine in Condition A or H1150 with rigid setups, sharp positive-rake carbide, heavy feeds and flood coolant; avoid dwelling — the alloy work-hardens, and H900 material cuts at roughly 30 % of AISI 1212.
Can 15-5 PH-H900 be welded?
Yes — weldability is rated very good (70/100). Readily GTAW/GMAW/EB welded without preheat using 15-5 PH or 17-4 PH filler; re-solution treat and age (or at minimum re-age) after welding to restore properties in the HAZ.
What surface finishes work on 15-5 PH-H900?
Takes a fine mechanical polish thanks to low inclusion content; passivate per AMS 2700/ASTM A967 after machining, and avoid electroplating in H900 unless baked for hydrogen embrittlement relief.
Can 15-5 PH-H900 be formed, bent or molded?
Cold form only in Condition A and expect high springback and forces; hot work at 1150–1200 °C and never finish below ~925 °C, followed by full solution treatment.
What is the maximum service temperature of 15-5 PH-H900?
15-5 PH-H900 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 15-5 PH Condition A and 15-5 PH-H900?
Condition A is the default condition — standard mill-supplied condition: soft-martensitic, machinable and formable, then age-hardened by the user. H900: choose for maximum strength and hardness — aerospace fittings, shafts, valve parts; least tough and most SCC-sensitive age. Yield strength is 795 MPa in Condition A versus 1,275 MPa in H900.
Can FabDigit make parts in 15-5 PH-H900?
Yes — 15-5 PH-H900 is available for CNC machining, sheet metal and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A564/A564M — Hot-Rolled and Cold-Finished Age-Hardening Stainless Steel Bars and Shapes (Type XM-12) — ASTM International (2019)
- ASTM A693 — Precipitation-Hardening Stainless Steel Plate, Sheet and Strip — ASTM International (2016)
- AMS 5659 — Steel, Corrosion-Resistant, Bars, Wire, Forgings 15Cr-4.5Ni-3.5Cu — SAE International (2018)
- EN 10088-3 / 1.4545 X5CrNiCu15-5 — CEN (2014)
- 15-5 PH Stainless Steel Product Data Bulletin — AK Steel / Cleveland-Cliffs (2015)
- Custom 15-5 PH Alloy Technical Datasheet — Carpenter Technology (2020)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- MMPDS-17 (Metallic Materials Properties Development and Standardization) — Battelle/FAA (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.