DIN 1.3343

3343 steel, also known as High Speed Steel (HSS) or Tungsten-Molybdenum Steel, is a type of tool steel known for its excellent wear resistance and hardness at high temperatures. 

Composition:

- Carbon (C): 0.78 - 0.88%

- Manganese (Mn): 0.15 - 0.40%

- Silicon (Si): 0.20 - 0.45%

- Chromium (Cr): 3.75 - 4.50%

- Vanadium (V): 1.75 - 2.20%

- Molybdenum (Mo): 4.50 - 5.50%

- Tungsten (W): 5.50 - 6.75%

Properties:

- Hardness: Typically around 60-65 HRC (Rockwell C)

- Density: ~8.2 g/cm³

- Tensile Strength: 1200-2200 MPa (174,000-319,000 psi)

- Yield Strength: ~800-1600 MPa (116,000-232,000 psi)

- Elongation: ~3-10% (depending on heat treatment)

Heat Treatment:

- Annealing: Heat to 850-900°C (1560-1650°F), furnace cool at a rate of no more than 10°C (18°F) per hour.

- Hardening: Preheat at 450-600°C (840-1110°F), then raise to 1150-1250°C (2100-2280°F) for 5-15 minutes, quench in air or oil.

- Tempering: Temper immediately after hardening. Typical tempering temperature ranges from 500-600°C (930-1110°F) for desired hardness and toughness.

Applications:

- 3343 steel is widely used in cutting tools such as drills, taps, reamers, milling cutters, saw blades, and broaches.

- It is suitable for high-speed machining operations where tools must maintain sharp cutting edges at elevated temperatures.

Machinability:

- 3343 steel is machinable in the annealed or fully hardened condition. It retains its hardness even at high temperatures, allowing for efficient machining operations.

Corrosion Resistance:

- 3343 steel has good resistance to corrosion due to its high chromium content, but it is not stainless and can rust if exposed to moisture.

Weldability:

- 3343 steel is generally not weldable due to its high carbon and alloy content. It can be difficult to achieve satisfactory welds, and precautions such as preheating and post-weld heat treatment are necessary.

3343 steel's combination of high hardness, wear resistance, and toughness makes it ideal for cutting tools operating at high speeds and temperatures, where maintaining sharpness and durability are critical.