Description
Alloy Geek 25-4-4 PH Precipitation Hardening Stainless Steel Standard
Alloy 25-4-4, also known as UNS S21904 or Alloy 25-4-4 PH, is a precipitation-hardening stainless steel alloy. It is a member of the PH (precipitation-hardening) stainless steel family, which means it can be heat treated to achieve specific mechanical properties. Alloy 25-4-4 is designed to offer a combination of high strength, corrosion resistance, and toughness.
The composition of Alloy 25-4-4 typically includes:
- Chromium (about 20-22%)
- Nickel (about 3.5-5.5%)
- Manganese (about 1.5% max)
- Silicon (about 1% max)
- Carbon (about 0.04-0.08%)
- Nitrogen (about 0.2-0.3%)
- Iron (balance)
Key features and characteristics of Alloy 25-4-4:
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Precipitation Hardening: Alloy 25-4-4 can be strengthened through precipitation hardening, a heat treatment process that allows it to achieve a range of mechanical properties.
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High Strength: The alloy offers substantial mechanical strength and can be customized to meet specific application requirements through heat treatment.
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Corrosion Resistance: Alloy 25-4-4 provides good corrosion resistance, especially in acidic and chloride-containing environments.
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Toughness: The alloy's toughness, along with its strength, makes it suitable for applications that require both mechanical performance and resistance to wear and impact.
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Weldability: Alloy 25-4-4 can be welded using common welding methods, though post-weld heat treatment might be required to restore the alloy's precipitation-hardened properties.
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Applications: Alloy 25-4-4 is used in industries such as aerospace, oil and gas, and medical equipment manufacturing. It's often chosen for applications requiring a combination of high-strength components and good corrosion resistance.
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Heat Treatment: Precipitation hardening can be achieved through aging at different temperatures to optimize mechanical properties.
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Forms: Alloy 25-4-4 is available in various forms, including sheets, plates, bars, and forgings.
Alloy 25-4-4's combination of strength, corrosion resistance, and toughness makes it suitable for applications where mechanical performance is essential. Its ability to be heat treated to achieve different mechanical properties allows it to be tailored to specific industrial needs. If you're considering using Alloy 25-4-4 for a particular project, consulting with materials experts or manufacturers is advisable to determine the best heat treatment and mechanical properties for your application.
Reference Material (RM): A reference material, or RM, is a material with a known composition or property that is used for informational purposes to look at analytical instruments, methods, or procedures. It serves as a point of comparison to ensure the accuracy and reliability of measurements. Reference materials can vary in terms of their level of characterization and traceability. Some reference materials may have well-defined properties, but they might not have undergone the rigorous testing and certification process that certified reference materials (CRMs) undergo. Reference Material chemical compositions are for information purposes.
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In summary, the main difference between a reference material and a certified reference material lies in the level of characterization, validation, and certification. CRMs have undergone a more comprehensive and rigorous testing process, resulting in certified values and uncertainties that can be confidently used for instrument calibration, quality control, and research. Reference materials, on the other hand, can provide a point of comparison but do not have the same level of certification and traceability as CRMs. When accuracy and traceability are critical, certified reference materials are preferred.