Material details

Carbide grades for tools and their properties

Low cobalt content (4–6%)

• High hardness
• High wear resistance
• Low toughness

Used for:

• High-speed machining
• Hard, abrasive materials (cast iron, hard non-ferrous metals)
• Cutting edges with sharp geometries

Medium cobalt content (6–10%)

• A good balance of hardness and toughness
• Highly versatile

Used for:

• General machining
• Milling, turning and drilling
• Medium-difficulty materials (unhardened and alloy steels)

High cobalt content (10–20%)

• Greater toughness
• Lower hardness
• Better resistance to impact and breakage

Used for:

• Interrupted cutting (discontinuous machining)
• Tough materials (stainless and heat-treated steels)
• Heavy-duty or vibration-prone operations

Properties

Heat resistance
Good (up to 800–1000°C)

Cutting speed
Medium

Abrasive-wear resistance
High

Hardness (HV)
1400–1800 HV

Chemical stability
Moderate

Ideal for
A wide range, including steels and stainless steels

Ceramic tool grades and their properties

White ceramic (Al2O3 – pure alumina)

• Very hard and thermally stable, but not very tough
• Hardness: ~1800–2000 HV

Used for:

• Machining high-speed steels and stainless steels

Pink ceramic (Al2O3 + Cr2O3)

• Like white ceramic, but slightly tougher and more wear-resistant
• Similar hardness: ~1800–2000 HV

Used for:

• Machining steels and hardened steels

Green ceramic (silicon nitride – Si3N4)

• Very tough and far more resistant to thermal shock than alumina.
• Hardness: ~1500–1600 HV

Used for:

• Machining glass, ceramics, hard metals and sintered materials

Properties

Heat resistance
Very high
(up to 1200–1400°C)

Cutting speed
Extremely high
(up to 5–10× that of carbide)

Abrasive-wear resistance
High

Hardness (HV)
1800–2500 HV
(depending on the grade)

Chemical stability
Excellent on high-temperature materials

Ideal for
Cast iron, superalloys, hard materials