About material
Material 1.7729 is a special alloy steel that falls into the category of both low-temperature and high-temperature materials. Here are some key details about this material:
- Chemical Composition:
- Contains approximately 0.17–0.23% carbon ©.
- Has a maximum silicon (Si) content of 0.4%.
- Contains 0.35–0.75% manganese (Mn).
- Has a maximum nickel (Ni) content of 0.2%.
- Contains trace amounts of phosphorus (P) and sulfur (S) (both less than 0.02%).
- Contains 0.9–1.2% chromium (Cr).
- Has 0.9–1.1% molybdenum (Mo).
- Contains 0.6–0.8% vanadium (V).
- Has 0.07–0.15% titanium (Ti).
- Contains a maximum of 0.2% aluminum (Al).
- Has a maximum copper (Cu) content of 0.02%.
- Contains trace amounts of arsenic (As) (between 0.001% and 0.01%).
- Has a maximum boron (B) content of 0.02%.
- Mechanical Properties (in quenched and tempered conditions):
- Tensile Strength (Rm): 820–1000 MPa.
- Yield Strength (Rp0.2): 660 MPa.
- Charpy V-notch Impact Toughness (KV) at +20°C: 27–40 J.
- Minimum Elongation at Fracture (A): 15%.
- Reduction of Area at Fracture (Z): 50%.
This material is commonly used for screws and other fasteners in applications with extreme temperatures, as its properties are optimized for such conditions.
