Comprensión de los grados de carburo de tungsteno para aplicaciones de herramientas de corte

When it comes to cutting tools, tungsten carbide is the go-to material for professionals who need strength, speed, and reliability.

But not all carbide tools are created equal. The grade of tungsten carbide you choose can greatly affect how your tool performs—and how long it lasts.

Whether you’re cutting aluminum, steel, or composites, using the right carbide grade is key to achieving the best results.

This guide helps you understand what carbide grades mean, why they are important, and how to choose the best grade for your job.

1. What Are Tungsten Carbide Grades?

Tungsten carbide grades refer to different mixtures of tungsten carbide and other materials (like cobalt), which affect the tool’s dureza, strength, toughness, and resistencia al desgaste.

Think of it like choosing the right type of steel: some are great for strength, others for flexibility. With tungsten carbide, the mix determines how the tool behaves.

Basic Ingredients:

Tungsten carbide (WC): The hard particles
Cobalt (Co): The binder that holds the particles together

Different ratios and grain sizes create different grades—some better for tough jobs, others better for precise finishing.

2. Why Do Grades Matter?

Using the wrong grade can result in:

Tool breakage
Premature wear
Mal acabado superficial
Low productivity
Higher costs

On the flip side, the right grade means:

Mayor vida útil de la herramienta
Better surface quality
Faster machining speeds
Improved dimensional accuracy

That’s why selecting the correct tungsten carbide grade is critical in any machining operation.

3. How Grades Are Classified

Tungsten carbide grades don’t follow a universal code, but most manufacturers use systems based on grain size, binder percentage, and application category. Here’s how they break down:

1). Grain Size (microstructure)

Ultra-fine (<0.5 µm): Great for sharp tools, high resistencia al desgaste, and finishing
Fine (0.5–1.0 µm): Good for moderate wear and strength balance
Medium (1–2 µm): General-purpose, suitable for many jobs
Coarse (>2 µm): Better for toughness, less wear resistance

2). Binder Content (Cobalt %):

6–10% Co: Higher dureza, lower toughness (best for hard materials)
10–20% Co: Greater toughness, better shock resistance

3). ISO Classification (for inserts):

P-grade: Steel
M-grade: Stainless steel
K-grade: Cast iron
N-grade: Non-ferrous (aluminum, copper)
S-grade: High-temp alloys (Inconel, titanium)
H-grade: Hardened materials

4. Common Tungsten Carbide Grades and Their Uses

Here’s a simplified reference chart showing typical carbide grades and what they’re good for:

Grade Type	Tamaño del grano	Cobalt %	Mejor para
Ultra-Fine (UF)	< 0.5 µm	6–10%	Finishing, sharp edges, aluminum, plastics
Fine Grain (F)	0.5–1 µm	6–12%	General purpose, light steel, copper
Medium Grain (M)	1–2 µm	10–15%	Steel, cast iron, versatile applications
Coarse Grain (C)	> 2 µm	15–20%	Heavy-duty, interrupted cuts, impact resistance

5. Choosing the Right Grade for Your Application

Here’s how to pick the proper carbide grade depending on the material you’re machining:

1). Aluminum & Non-Ferrous Materials

Use ultra-fine grain carbide with polished flutes
Lower cobalt content for sharper edges
Ideal for high RPM and clean finishes

2). Steel (Mild, Alloyed)

Choose medium grain carbide with moderate binder
Look for coatings like TiAlN or AlCrN for heat resistance

3). Stainless Steel

Needs a balance of hardness and toughness
Go with fine grain, 10–15% cobalt
Avoid sharp corners—use rounded profiles

4). Cast Iron

Use harder grades, medium or fine grain
Sharp tools are less effective—opt for edge strength

5). Titanium & High-Temp Alloys

Require ultra-fine carbide with strong coatings
Avoid chip welding with DLC or TiAlN coatings

6). Hardened Steel

Needs low cobalt, high hardness carbide
Often paired with ceramic or PCD tips

6. Coatings Also Matter

Even the best carbide grade needs the right coating to perform well.

Here are some popular coating types used on carbide tools:

Revestimiento	Mejor para	Key Benefits
Estaño	General use	Mayor dureza
TiAlN	Steel, high-temp alloys	Heat resistance, long tool life
AlTiN	Hardened steels	Strong under high heat, dry cutting
Contenido descargable	Aluminum, plastics	Reduces sticking, smooth cutting