Product Description
15-5PH (1.4545) is a premium martensitic precipitation hardening stainless steel containing approximately 15% chromium, 5% nickel, and 4% copper with additions of niobium. Developed as an improved variant of 17-4PH, this high-performance alloy offers superior toughness, especially in the transverse direction, better ductility, and excellent formability while maintaining comparable corrosion resistance and high strength properties. The reduced delta ferrite content and controlled inclusion size and shape in 15-5PH contribute to its enhanced mechanical properties.
In its solution annealed condition, 15-5PH is supplied with a martensitic structure that can be further strengthened through a simple, low-temperature aging heat treatment process. This precipitation hardening mechanism allows the material to develop high strength and hardness while maintaining good corrosion resistance. The material can be easily fabricated in its annealed state and then hardened with minimal distortion through a single, low-temperature heat treatment.
The corrosion resistance of 15-5PH is comparable to that of Type 304 stainless steel in most environments and is generally superior to that of the hardenable 400 series stainless steels. This combination of high strength and good corrosion resistance makes 15-5PH an ideal choice for applications in aerospace, medical, defense, oil and gas, food processing, petrochemical, power generation, and general industrial sectors where both properties are essential.
FUSHUN METAL supplies 15-5PH stainless steel in various product forms and conditions to meet the diverse requirements of demanding applications. Our high-quality material provides reliable performance in critical components where the combination of strength, toughness, and corrosion resistance is paramount.
Applications
15-5PH stainless steel is widely used across multiple industries due to its exceptional combination of high strength, good corrosion resistance, and superior toughness compared to 17-4PH. The material is particularly valuable in applications requiring high mechanical properties and moderate corrosion resistance at service temperatures up to 600°F (315°C).
Key applications for 15-5PH stainless steel include:
- Aerospace Industry: Aircraft components, helicopter parts, landing gear components, fasteners, engine parts, structural components, and marine gas turbine compressor sections where high strength-to-weight ratio, corrosion resistance, and toughness are essential requirements.
- Oil and Gas Production: Valves, pump components, fasteners, fittings, and other critical components exposed to corrosive environments where both strength and corrosion resistance are vital.
- Power Generation: Turbine components, shafts, fasteners, and other critical parts requiring high reliability and corrosion resistance.
- Food Processing Industry: Machinery components, shafts, fasteners, and equipment parts that require both strength and corrosion resistance while meeting sanitary requirements.
- Medical and Biomedical Equipment: Surgical tools, dental instruments, and medical device components requiring high strength and good corrosion resistance.
- Chemical Processing: Valves, pump components, fasteners, and fittings used in chemical processing equipment handling moderately corrosive media.
- Paper Mill Equipment: Various components exposed to corrosive environments while requiring high strength and reliability.
- Mechanical Components: Gears, shafts, cylinders, hollow shafts, and other high-strength mechanical parts benefiting from the material’s high hardness, strength, and corrosion resistance.
- Automotive Industry: High-performance fasteners, chassis components, and other critical parts requiring high strength and corrosion resistance.
- Nuclear Applications: Various components used in nuclear waste processing and storage where high reliability and corrosion resistance are essential.
The versatility of 15-5PH stainless steel makes it an excellent choice for applications where conventional austenitic stainless steels lack sufficient strength and where conventional martensitic stainless steels lack adequate corrosion resistance or toughness. Its improved toughness in both longitudinal and transverse directions in both base metal and welds, along with its ability to be machined in the annealed condition and then hardened with minimal distortion, provides significant manufacturing advantages in producing complex, precision components.
Standards
15-5PH stainless steel conforms to numerous international standards and specifications, ensuring consistent quality and performance in demanding applications:
American Standards:
- UNS: S15500
- AMS 5659: Steel, Corrosion-Resistant, Bars, Wire, Forgings, Mechanical Tubing, and Rings
- AMS 5862: Steel, Corrosion-Resistant, Sheet, Strip, and Plate
- ASTM A693: Standard Specification for Precipitation-Hardening Stainless and Heat-Resisting Steel Plate, Sheet, and Strip (Grade XM-12)
- ASTM A639: Standard Specification for Precipitation-Hardening Stainless Steel Billets and Bars for Forging
European Standards:
- EN Number: 1.4545
- EN 10088-3: Stainless steels – Part 3: Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products of corrosion resisting steels for general purposes
- EN 10151: Stainless steel strip for springs
German Standards:
- WL 1.4545.4: Solution annealed and hardened condition
- WL 1.4545.9: Solution annealed condition
Industry-Specific Standards:
- Aerospace: Compliant with various aerospace industry specifications
- Defense: DFARS Compliant material available
These comprehensive standards ensure that 15-5PH stainless steel from FUSHUN METAL meets the rigorous requirements for use in critical applications across various industries, particularly in aerospace and other high-performance sectors.
Material Designation and Chemical Composition
15-5PH stainless steel is known by various designations in different standards and specification systems:
| Standard System | Designation |
|---|---|
| UNS | S15500 |
| EN/DIN | 1.4545 |
| ASTM | XM-12 |
The chemical composition of 15-5PH stainless steel is carefully controlled to ensure optimal performance in demanding applications:
| Element | Minimum (%) | Maximum (%) |
|---|---|---|
| Carbon (C) | – | 0.07 |
| Chromium (Cr) | 14.0 | 15.5 |
| Nickel (Ni) | 3.5 | 5.5 |
| Copper (Cu) | 2.5 | 4.5 |
| Niobium (Columbium) + Tantalum (Nb+Ta) | 0.15 | 0.45 |
| Manganese (Mn) | – | 1.0 |
| Silicon (Si) | – | 1.0 |
| Phosphorus (P) | – | 0.04 |
| Sulfur (S) | – | 0.03 |
| Molybdenum (Mo) | – | 0.50 |
| Iron (Fe) | Balance | – |
The carefully balanced composition of 15-5PH stainless steel, with its high chromium content for corrosion resistance and strategically added copper and niobium for precipitation hardening capability, provides the unique combination of properties that make this alloy valuable for demanding applications requiring both high strength and good corrosion resistance. The precise control of composition, particularly the minimized delta ferrite content, contributes to the superior toughness of 15-5PH compared to 17-4PH.
Physical and Mechanical Properties
15-5PH stainless steel offers an exceptional combination of high strength, good corrosion resistance, and excellent toughness. The mechanical properties can be tailored through various aging heat treatments to meet specific application requirements.
Physical Properties
| Property | Value |
|---|---|
| Density | 7.8 g/cm³ (0.282 lb/in³) |
| Melting Range | 1404-1440°C (2560-2625°F) |
| Thermal Conductivity at 150°C | 17.8 W/m·K |
| Coefficient of Thermal Expansion (21-93°C) | 10.8 × 10⁻⁶ /K |
| Modulus of Elasticity | 196 GPa (28.5 × 10⁶ psi) |
Mechanical Properties
The mechanical properties of 15-5PH stainless steel vary significantly based on the heat treatment condition. Below are typical properties for various common heat treatment conditions:
| Condition | Ultimate Tensile Strength, MPa (ksi) | 0.2% Yield Strength, MPa (ksi) | Elongation, % | Hardness, HRC (HBW) |
|---|---|---|---|---|
| H900 (aged at 482°C/900°F) | 1310 min (190 min) | 1170 min (170 min) | 10 min | 40 min (388 min) |
| H925 (aged at 496°C/925°F) | 1170 min (170 min) | 1070 min (155 min) | 10 min | 38 min (375 min) |
| H1025 (aged at 552°C/1025°F) | 1070 min (155 min) | 1000 min (145 min) | 12 min | 35 min (331 min) |
| H1075 (aged at 580°C/1075°F) | 1000 min (145 min) | 860 min (125 min) | 13 min | 32 min (311 min) |
| H1100 (aged at 593°C/1100°F) | 965 min (140 min) | 795 min (115 min) | 14 min | 31 min (302 min) |
| H1150 (aged at 621°C/1150°F) | 930 min (135 min) | 725 min (105 min) | 16 min | 28 min (277 min) |
| H1150M (double aged) | 795 min (115 min) | 520 min (75 min) | 18 min | 24 min (255 min) |
Heat Treatment
15-5PH stainless steel achieves its high strength through a simple heat treatment process that involves solution annealing followed by aging (precipitation hardening). The standard heat treatment procedures include:
- Solution Annealing (Condition A): Heating to 1038-1065°C (1900-1950°F) followed by cooling to room temperature. In this condition, the material possesses a martensitic structure.
- Aging Treatment: Solution-annealed material is subjected to one of several aging treatments to develop the desired combination of strength, hardness, and toughness. Common aging treatments include:
- H900: Aging at 482°C (900°F) for 1 hour, followed by air cooling. Produces maximum hardness and strength.
- H925: Aging at 496°C (925°F) for 4 hours, followed by air cooling.
- H1025: Aging at 552°C (1025°F) for 4 hours, followed by air cooling.
- H1075: Aging at 580°C (1075°F) for 4 hours, followed by air cooling.
- H1100: Aging at 593°C (1100°F) for 4 hours, followed by air cooling.
- H1150: Aging at 621°C (1150°F) for 4 hours, followed by air cooling.
- H1150M: Two-step treatment involving a 2-hour exposure at 760°C (1400°F), air cooling, followed by a 4-hour exposure at 621°C (1150°F), and final air cooling.
The aging treatment temperature determines the final mechanical properties. Lower aging temperatures (H900, H925) produce higher strength and hardness but lower toughness and ductility. Higher aging temperatures (H1075, H1150) result in improved toughness and ductility at the expense of some strength. H1150 and H1150M conditions provide improved toughness and resistance to stress corrosion cracking, making them preferred for applications in aggressive environments.
It’s important to note that 15-5PH should not generally be used in the solution-annealed condition (Condition A). In this condition, the material has an untempered martensite structure with lower ductility and is more susceptible to stress corrosion cracking than aged material.
Available Dimensions
FUSHUN METAL supplies 15-5PH stainless steel in a wide range of product forms and dimensions to meet diverse application requirements:
Plate and Sheet
| Product Form | Thickness | Width | Length |
|---|---|---|---|
| Plate | 4.0 mm – 100 mm (0.157″ – 4″) | Up to 2,500 mm (98″) | Up to 10,000 mm (394″) |
| Sheet | 0.38 mm – 3.18 mm (0.015″ – 0.125″) | Up to 1,500 mm (59″) | Up to 6,000 mm (236″) |
| Strip | 0.1 mm – 3.0 mm (0.004″ – 0.118″) | Up to 600 mm (24″) | Coil form or cut lengths |
Bar and Rod
| Product Form | Diameter/Dimension | Length |
|---|---|---|
| Round Bar | 12.7 mm – 300 mm (0.5″ – 12″) | Up to 6,000 mm (236″) |
| Square Bar | 10 mm – 150 mm (0.394″ – 6″) | Up to 6,000 mm (236″) |
| Flat Bar | Thickness: 5 mm – 100 mm (0.197″ – 4″) Width: 10 mm – 300 mm (0.394″ – 12″) |
Up to 6,000 mm (236″) |
| Hexagonal Bar | 10 mm – 100 mm (0.394″ – 4″) across flats | Up to 6,000 mm (236″) |
Forgings and Special Shapes
FUSHUN METAL also provides custom forgings and special shapes in 15-5PH stainless steel according to customer specifications:
- Open die forgings
- Closed die forgings
- Rings and discs
- Custom profiles
- Machined components
All products are supplied in the solution annealed condition (Condition A) unless otherwise specified. Age hardening heat treatments can be performed upon request to achieve specific mechanical properties. Custom dimensions, tolerances, and surface finishes are available to meet your specific requirements.
Fabrication Information
15-5PH stainless steel can be fabricated using conventional methods, but there are some important considerations to ensure optimal performance of the finished components:
Machining
15-5PH stainless steel has good machinability in the solution-annealed condition, although not as good as austenitic stainless steels due to its higher strength. The following recommendations apply:
- Both high-speed steel and carbide tools are suitable for machining 15-5PH.
- Rigid tooling setups are recommended to minimize vibration.
- Use coolants and lubricants designed for stainless steel machining.
- Machining after age hardening is possible but more difficult, requiring slower speeds and more rigid setups.
- For maximum softness to provide better machinability, the H1150M condition can be used.
Forming
Due to its high strength, 15-5PH has limited formability in the annealed condition:
- Cold forming should be limited to mild operations in the annealed condition.
- Forming is more easily accomplished in the overaged condition (such as H1150), as opposed to the annealed condition.
- Hot forming can be performed at temperatures between 950-1200°C (1742-2192°F).
- After hot forming, full heat treatment (solution annealing followed by aging) is required to restore optimal properties.
Welding
15-5PH stainless steel can be readily welded using conventional inert gas methods used for stainless grades:
- Suitable welding processes include GTAW (TIG), GMAW (MIG), SMAW (stick), and other standard methods.
- Preheating is not usually required.
- If matching filler material is used, properties comparable to those of the parent metal can be produced in the weld by post-weld precipitation hardening heat treatment.
- For non-matching filler, an austenitic stainless steel such as Type 308L can be used for improved ductility, although this will not produce the precipitation hardening response.
- Post-weld heat treating is needed to produce the various precipitation hardened heat treatment properties.
- More uniform mechanical properties can be obtained by solution annealing the material before conducting precipitation hardening heat treatments after welding.
Cutting
Proper cutting methods are important to avoid potential issues with 15-5PH:
- Water jet or saw cutting are the safest methods for cutting.
- Wet abrasive cutting is typically acceptable but may produce small cracks due to local overheating.
- Plasma torch cutting may create cracking in the as-annealed condition, especially in thicker sections. These cracks may propagate far into the base material.
- Aging the material at 621°C (1150°F) or higher before torch cutting can minimize the cracking risk.
- The torch cut edge should be cleaned by grinding or milling with appropriate clean-up allowance.
Corrosion Resistance and Service Limitations
15-5PH stainless steel offers good corrosion resistance properties that make it suitable for a wide range of applications, but it also has important service limitations that should be considered:
Corrosion Resistance
- The corrosion resistance of 15-5PH is comparable to that of Type 304 stainless steel in most media and superior to that of the hardenable 400 series stainless steels.
- In many corrosive environments, its resistance is better than that of 410 stainless steel and comparable to that of 302 and 304 stainless steels.
- The general level of corrosion resistance is best in the fully hardened condition and decreases slightly as the aging temperature is increased.
- Material in the annealed condition should not generally be put into service due to its untempered martensite structure, which makes it less ductile and more susceptible to stress corrosion cracking than aged material.
Service Limitations
- Temperature Limitations: 15-5PH is applicable in a temperature range from -200°C to 300°C (-328°F to 572°F). High strength is maintained to approximately 316°C (600°F).
- Stress Corrosion Cracking: As with other precipitation hardening stainless steels, 15-5PH is more susceptible to stress corrosion cracking at peak strength. In applications where chloride stress corrosion cracking is a possibility, the material should be precipitation hardened at higher temperatures (H1075, H1150) to produce the lowest hardness compatible with the intended end use.
- Oxidation: The oxidation resistance of 15-5PH is superior to that of 12% chromium alloys like Type 410 but slightly inferior to that of Type 430. Precipitation hardening can produce surface oxidation.
Application Recommendations
- For applications with potential for stress corrosion cracking, use higher aging temperatures (H1075, H1150) to achieve better resistance at the expense of some strength.
- Avoid using the material in the as-annealed condition in service.
- For maximum formability and machinability, consider using the H1150M condition.
- For the best combination of strength and corrosion resistance, the H900 or H925 conditions are typically preferred.
- When welding is required, consider post-weld heat treatment to restore optimal properties.
Why Choose FUSHUN METAL for 15-5PH Stainless Steel
When selecting a supplier for premium 15-5PH precipitation hardening stainless steel, FUSHUN METAL stands as your preferred partner for several compelling reasons:
Superior Quality Assurance
At FUSHUN METAL, we implement rigorous quality control processes throughout our production chain. Our 15-5PH stainless steel undergoes comprehensive testing including chemical analysis, mechanical testing, microstructure examination, and corrosion testing to ensure full compliance with international standards and specifications. This meticulous attention to quality guarantees that our products consistently deliver the exceptional performance required in the most demanding applications, particularly in aerospace and other critical sectors.
Metallurgical Expertise
Our team of metallurgical specialists possesses extensive experience and knowledge in the production and processing of precipitation hardening stainless steels. This expertise enables us to provide valuable technical support to help you select the optimal material specifications and heat treatment conditions for your specific application requirements. We understand the critical factors that influence the performance of 15-5PH stainless steel and can help you optimize your designs to take full advantage of its superior properties compared to 17-4PH, including its enhanced toughness and ductility.
Comprehensive Product Range
FUSHUN METAL offers one of the most extensive ranges of 15-5PH stainless steel products available, including plate, sheet, strip, bar, and custom components. This diverse product portfolio allows you to source all your precipitation hardening stainless steel requirements from a single, reliable supplier, streamlining your procurement process and ensuring consistency across your projects. Whether you need standard stock sizes or custom dimensions, we can meet your specific requirements with precision and reliability.
Advanced Heat Treatment Capabilities
We provide 15-5PH stainless steel in both the solution-annealed condition and in various age-hardened conditions to meet your specific strength and corrosion resistance requirements. Our advanced heat treatment facilities ensure precise control of temperatures and processing parameters, resulting in consistent and predictable material properties. Whether you need maximum strength (H900) or improved toughness and stress corrosion resistance (H1150), we can deliver the exact properties your application demands.
Value-Added Services
Beyond supplying premium materials, we offer a range of value-added services including custom cutting, machining, heat treatment, surface finishing, and non-standard dimensions to meet your specific requirements. Our ability to provide tailored solutions helps you optimize your manufacturing processes and reduce overall costs. For aerospace and other critical applications, we can provide full material traceability and certification to meet your quality assurance requirements.
For your next project requiring the exceptional combination of high strength, good corrosion resistance, and superior toughness that 15-5PH stainless steel provides, we invite you to contact our technical team to discuss your specific requirements. Our experts are ready to help you select the optimal material specifications and heat treatment conditions, providing the premium quality products you need for reliable, long-term performance in even the most demanding applications.
