Application Scope of Cemented Carbide

The applications of cemented carbide primarily fall into three major categories: cutting tools, mining blades, and custom-shaped materials. Different types of cemented carbide, depending on their composition and properties, are utilized in distinct application fields.

Type 1: WC-Co Cemented Carbide (YG Series)

WC-Co (YG-type) cemented carbide is primarily used for machining cast iron, non-ferrous metals, and non-metallic materials. When machining cast iron, It break into fragments and subjecting the tool to significant impact, with cutting forces and heat concentrated near the cutting edge. Key characteristics of YG alloys include:

1）Higher transverse rupture strength and impact toughness (compared to YT-type alloys). reducing the cutting lip cracking during cutting.

2）Superior thermal conductivity. facilitating heat dissipation from the cutting edge, lowering temperatures, and preventing overheating-induced softening.

3）Excellent grindability. enabling sharp cutting edges, ideal for non-ferrous metals and fiber-reinforced composites.

Effect of Cobalt Content:

Higher cobalt content: Enhances transverse rupture strength, impact toughness, and fatigue strength, suitable for rough machining under impact/vibration.

Lower cobalt content: Improves wear resistance and heat resistance, ideal for continuous finishing operations.

Type 2: WC-TiC-Co Cemented Carbide (YT Series)

YT-type alloys are designed for machining ductile materials like steel, where high plastic deformation and friction generate intense heat. Key features:

1）Higher hardness and heat resistance compared to YG alloys, with superior high-temperature strength and oxidation resistance.

2）Excellent wear resistance for steel machining. Lower thermal conductivity retains heat in the chip, promoting chip softening for smoother cutting.

Adjustable composition:

Higher cobalt + lower TiC: Increased strength for rough machining.

Lower cobalt + higher TiC: Enhanced wear/heat resistance for finishing.

Type 3: WC-TaC(NbC)-Co Cemented Carbide

Adding small amounts of carbides (TaC, NbC, Cr3C2, etc., 0.5–3%) to WC-Co alloys improves performance by:

1）Refining grain structure, maintaining fine grains and preventing recrystallization.

2）Boosting hardness and wear resistance without sacrificing toughness.

3）Enhancing high-temperature performance and forming a self-repairing oxide layer to resist adhesion/diffusion wear.

Applications:

Machining hard cast iron and alloy cast iron.

Low-cobalt alloys with 3–10% TaC(NbC) serve as universal grades.

Type 4: WC-TiC-TaC(NbC)-Co Cemented Carbide (YW Series)

Incorporating TaC into WC-TiC-Co alloys yields "universal alloys" (YW-type) with balanced properties:

1）Increased transverse rupture strength, fatigue resistance, and impact toughness.

2）Enhanced heat resistance, high-temperature hardness, and oxidation resistance.

3）Improved resistance to crater wear and flank wear.

Applications:

Machining steels (primary use), cast iron, and non-ferrous metals.

Ideal for difficult-to-machine materials: high-alloy steels, heat-resistant alloys, and specialty cast irons.

Higher cobalt variants: Suitable for roughing and interrupted cutting of challenging materials.

Summary:

YG (WC-Co): Optimal for cast iron/non-ferrous metals, balancing toughness and heat dissipation.

YT (WC-TiC-Co): Specialized for steels, prioritizing hardness and heat resistance.

TaC/NbC-modified: Enhanced wear resistance and versatility for demanding applications.

YW (WC-TiC-TaC-Co): Universal grade for mixed-material machining and extreme conditions.

Each type leverages unique compositions to address specific machining challenges, ensuring high performance across industrial applications.