What are the key features and uses of high-speed steel?

When it comes to spiral cutterheads, blade material is more than just a spec — it's the core of performance, durability, and finish quality. At Sheartak, we carefully select insert grades based on what our customers need: cleaner cuts, longer tool life, and smoother finishes across a wide range of materials.

Here’s a quick guide to the most common high-speed steel (HSS) grades used in cutting tools — and why we rely on premium materials for our cutterhead inserts.

AISI 4241 (W1)

• Type: Low-end high-speed steel
• Common Elements:
  • C: ~0.92%, Cr: ~4.0%, Mo: ~1.3%, W: ~1.1%
• Hardness: Moderate
• Performance:
  • Basic hardness and wear resistance
  • Mostly found in DIY drill bits or hobby tools
• Verdict: Not suitable for long-lasting industrial cutterheads — wears too quickly under load.

• Use: Light-duty cutting tools

AISI 4341 – Entry-Level Upgrade

• Type: Mid-range high-speed steel
• Improvements Over 4241: Similar to 4241 but slightly higher W (~1.5%) and Mo (~1.5%)
• Performance:
  • Improved red hardness (heat resistance)
  • Used for general-purpose tools like consumer-grade drill bits

• Use: General-purpose drill bits and cutting tools

W6Mo5Cr4V2 (6542 / M2 Equivalent)

• Type: Standard high-performance HSS
• Also Known As: T6542 (China), equivalent to AISI M2
• Composition: W: ~6%, Mo: ~5%, Cr: ~4%, V: ~2%
• Performance:
  • Excellent wear resistance and edge retention
  • Good balance of toughness and hardness
  • Industry-standard high-speed steel

• Use: Widely used in industrial cutters, Milling cutters, twist drills, taps, reamers

M35 – Cobalt Enhanced (Co5%)

• Type: Cobalt-alloyed HSS 
• Key Elements: Same as M2 (6542) plus 4.8–5% Co
• Benefits:
  • Increased red hardness
  • Better for stainless steel and hardened materials

• Use: Industrial drills, end mills, tapping tools

M42 (Co8%)

• Type: High-cobalt HSS 
• Key Elements: C: ~1.1%, Co: ~8%, Mo: ~9.5%, V: ~1.15%
• Benefits:
  • Exceptional hot hardness, highest wear resistance
  • Built for high-speed, heavy-duty cuts in extreme conditions

• Use: Aerospace, stainless, titanium, hardened alloys

🔩 Summary Table