HII
Home / HII
Products
Special Steels Division
Wire Division
Product Description:
HII is a high-speed tool steel known for its excellent wear resistance, hardness, and ability to maintain its cutting properties at elevated temperatures. It is commonly used in the manufacture of cutting tools, especially those that operate at high speeds or under high heat. The alloy is designed for applications that demand excellent performance even in extreme working conditions, such as machining, drilling, and milling operations. It is part of the high-speed steel family (HSS), offering high wear resistance, hardness, and toughness, especially at elevated temperatures.
Features:
- High Wear Resistance: HII tool steel exhibits excellent wear resistance, making it ideal for cutting tools that are subjected to high abrasion.
- High Hardness: Can be heat treated to achieve high hardness levels (up to 62 HRC), providing superior cutting performance.
- Heat Resistance: It maintains its hardness and cutting ability even at elevated temperatures, which is a hallmark of high-speed steels.
- Good Toughness: HII offers good toughness, ensuring the material can handle the impact and stresses associated with cutting operations.
- Excellent Cutting Performance: Due to its hardness and heat resistance, HII is perfect for manufacturing tools that need to retain their sharpness in demanding conditions.
Specifications:
- ASTM A681: Standard Specification for Tool Steel, High-Speed, covering grades like HII.
- SAE J437: Standard for high-speed steels, including HII
- UNS T12002: Unified Numbering System designation for HII tool steel.
Composition of HII Tool Steel:
| Element | Percentage |
|---|---|
| Carbon (C) | 0.80 – 1.00 |
| Chromium (Cr) | 4.00 – 5.50 |
| Molybdenum (Mo) | 5.00 – 6.00 |
| Vanadium (V) | 1.00 – 2.00 |
| Manganese (Mn) | 0.25 – 0.45 |
| Silicon (Si) | 0.20 – 0.35 |
| Iron (Fe) | Balance |
Physical Properties:
| Property | Value |
|---|---|
| Density | 8.0 g/cm³ |
| Melting Point | 2750°F (1510°C) |
| Hardness (Rockwell C) | 62 HRC (maximum) |
| Tensile Strength (Ultimate) | 250,000 psi (1724 MPa) |
| Yield Strength | 220,000 psi (1517 MPa) |
| Elongation | 6-8% |
| Modulus of Elasticity | 200 GPa |