17-7PH
17-7PH (UNS S17700) is a precipitation-hardening stainless steel known for its high strength and good corrosion resistance. It is commonly used in applications requiring high tensile strength and fatigue resistance, such as aerospace components, automotive parts, and industrial machinery. This alloy meets various standards including AMS 5528, DIN/EN 1.4568, JIS SUS 632J1, and AISI 631, reflecting its versatility and reliability in demanding environments.
Composition
- Aluminum (Al): Min 0.75%, Max 1.50%
- Manganese (Mn): Max 1.00%
- Phosphorus (P): Max 0.05%
- Silicon (Si): Max 1.00%
- Nickel (Ni): Min 6.75%, Max 7.75%
- Sulfur (S): Max 0.03%
- Carbon (C): Max 0.09%
- Chromium (Cr): Min 16.00%, Max 18.00%
Properties
- Density: Approximately 8.0 g/cm³.
- Thermal Conductivity: ~16 W/m·K.
- Tensile Strength: High tensile strength due to precipitation hardening.
- Corrosion Resistance: Good resistance to oxidation and corrosion in various environments.
- Hardness: Typically Rockwell C 35 to 45, depending on heat treatment.
Applications
- 17-7PH is used for structural components and aerospace applications where high strength and resistance to corrosion are essential.
Advantages
- High Strength: Excellent strength-to-weight ratio due to precipitation hardening.
- Corrosion Resistance: Good performance in various corrosive environments.
- Versatility: Suitable for a wide range of applications due to its mechanical properties.
Limitations
- Cost: Higher cost compared to some other stainless steels due to alloying and processing.
- Machinability: More difficult to machine compared to standard stainless steels due to its hardness.