Description
15 – 5 PH® Stainless Steel , UNS S15500, XM-12
Stainless steel 15-5 PH, also known as UNS S15500 or XM-12, is a modification of 17-4 PH developed in the 60’s. UNS S15500 stainless steel has a more refined microstructure as a result of the remelting process in which it was developed. This refined structure enhances toughness, especially in the transverse direction of the material. 15-5PH also has excellent corrosion resistance, good fabricating characteristics and low temperature hardening which makes Stainless Steel 15.5 PH the preferred alloy for many industries.
The composition of 15/5PH includes small amounts of carbon, manganese, phosphorus, columbium (or niobium), tantalum, silicon and sulfur. 15/5 PH can be forged, welded and formed. Machining may be performed in the solution-annealed state or in the final heat treat condition. Desired mechanical properties such as ductility and strength can be achieved through heating the material at various temperatures.
UNS S15500 is a martensitic precipitation hardening grade. Martensitic stainless steels were designed as a type of alloy which is corrosion resistant and could also be hardened through heat treatment.
Chemical Composition
| Element | Content (%) |
| Iron, Fe | 75 |
| Chromium, Cr | 14.48 |
| Nickel, Ni | 4.5 |
| Copper, Cu | 3.5 |
| Manganese, Mn | ≤1 |
| Silicon, Si | ≤1 |
| Nb + Ta | 0.3 |
| Carbon, C | ≤0.07 |
| Phosphorous, P | ≤0.04 |
| Sulfur, S | ≤0.03 |
- 15-5 PH Mechanical Properties
| Condition | Ultimate Tensile Strenght | Yield Strength | Elongation | Reduction of Area | Hardness Brinell | Hardness Rockwell |
| H900 | 190,000 | 170,000 | 6 | 15 | 388 | C40 |
| H1025 | 155,000 | 125,000 | 8 | 27 | 331 | C35 |
| H1075 | 145,000 | 125,000 | 9 | 28 | 311 | C32 |
| H1150 | 135,000 | 105,000 | 11 | 30 | 277 | C28 |
| H1150-M | 115,000 | 75,000 | 14 | 35 | 255 |
Industries that use 15.5PH include:
- Aerospace , Chemical, Food processing, General metal working, Paper industries, Petrochemical.
Products partially or completely constructed of 15-5PH include:
- Aircraft components, Cylinders, Engine parts, Fittings, Gears, Hallow shafts, Marine gas turbine, compressor sections, Paper mill equipment, Shafts, Valves.
