Tungsten carbide inserts are essential components used in various industries for cutting, shaping, and machining applications. Known for their exceptional hardness, wear resistance and durability, tungsten carbide inserts are manufactured through a meticulous process that involves several key steps. Let’s explore how tungsten carbide inserts are manufactured from start to finish.
Brief background on tungsten carbide inserts
Tungsten carbide inserts are a type of cutting tool used in machining applications such as turning, milling and drilling. They are made from cemented carbides, which are composites of extremely hard carbide particles bonded together by a ductile cobalt metal matrix.
The hardness of tungsten carbide is comparable to diamond. It maintains strength and rigidity at high machining temperatures. Carbide inserts have largely replaced high-speed steel tools due to better wear resistance, higher cutting speeds and lower cost per part.
Cemented carbide inserts enable efficient machining of materials from soft plastics to hard steels, nickel alloys, titanium alloys and more. Their unique properties make them indispensable for today’s manufacturing.
Applications of using tungsten carbide blade
Turning – Excellent for turning operations on various metals including steel, stainless steel, cast iron, aluminum, titanium and high-temperature alloys.
Milling – Ideal for face milling, slotting, shoulder milling, and profile milling of alloys and exotic metals.
Drilling – Suitable for drilling most metal alloys, stack drilling and deep hole drilling.
Cutting tools – Used to make indexable end mills, saw blades, broaches and router bits.
Prototyping – CNC machining of prototypes from plastics, wood, aluminum and other non-ferrous alloys.
Benefits of using tungsten carbide blade
Excellent hardness: Tungsten carbide is renowned for its excellent hardness. It is one of the hardest materials, with a Mohs hardness second only to diamond. This hardness enables tungsten carbide inserts to withstand high levels of wear and abrasion, making them an ideal choice for cutting, drilling and machining resilient materials.
Excellent wear resistance: Tungsten carbide inserts have excellent wear resistance, allowing them to maintain sharp cutting edges and performance over extended periods of use. This wear resistance significantly extends the service life of inserts, minimizing the need for frequent replacement and improving productivity.
High strength and toughness: Tungsten carbide inserts possess high strength and toughness, enabling them to withstand heavy loads and resist fracturing or damage. They can withstand harsh cutting conditions, including high-speed machining and intermittent cutting, without impacting performance or structural integrity.
Multifunctionality: Tungsten carbide inserts come in various shapes, sizes and geometries, giving them versatility for many applications. Their designs can meet specific cutting demands such as turning, milling, thread cutting, grooving, etc. This multifunctionality makes tungsten carbide inserts suitable for industries ranging from metalworking and woodworking to mining and construction.
Heat and chemical resistance: Tungsten carbide has excellent heat and chemical corrosion resistance properties. This makes tungsten carbide inserts suitable for cutting and machining applications involving heat-resistant alloys, stainless steels and other challenging materials. They can withstand high temperatures without softening or losing cutting ability.
Improved productivity: With their hardness, wear resistance and toughness characteristics, tungsten carbide inserts can improve productivity. They enable faster cutting speeds, longer tool life and reduced downtime for insert changes, thereby enhancing efficiency and cost savings across industries.
Customizable coating options: Tungsten carbide inserts can be coated with various materials like titanium nitride (TiN), titanium carbonitride (TiCN) or diamond-like carbon (DLC). These coatings further enhance insert performance through increased wear resistance, reduced friction and higher surface hardness.
Consistent cutting performance: Tungsten carbide inserts provide consistent and predictable cutting performance to ensure machining operation precision and quality. They deliver stable and reproducible results, reducing the need for frequent adjustments and process control optimization.
Manufacturing Process Steps
（1）Raw Material Preparation
The main raw materials are tungsten powder and cobalt powder. Sometimes small amounts of titanium powder, tantalum powder and other alloying elements are added to adjust the final properties. Tungsten provides high hardness and cobalt as the binder phase improves toughness.
（2）Powder Blending
According to the composition ratios of different grades, the tungsten powder, cobalt powder, etc. are precisely measured and thoroughly mixed using a ball mill. Uniform cobalt distribution is critical.
（3）Compacting
The uniformly blended powder is compacted under high pressure into the desired geometry, achieving around 50-70% of theoretical density.
（4）Sintering
The compacted tungsten carbide-cobalt powder preforms are sintered at 1300-1600°C in a hydrogen or vacuum protective atmosphere. The cobalt binder phase melts, fusing the solid tungsten carbide particles together to form a dense tungsten carbide matrix.
（5）Grinding
The sintered tungsten carbide preforms are ground to achieve the insert shape design and sharp cutting edges. Grinding wheels and diamond wheels enable efficient high-rate machining.
（6）PVD/CVD Coating
Typically a PVD or CVD coating process is used to coat inserts with TiN, TiCN, TiAlN and other coatings on the inserts to improve oxidation and wear resistance.
（7）Testing
Comprehensive testing of insert dimensions, surface finish, internal defects, hardness, etc. is conducted to ensure standards are achieved.
（8）Packaging
Qualified inserts are protectively packaged for transportation and storage.
Design Considerations
Several design factors must be optimized when engineering tungsten carbide inserts for certain applications:
Carbide grade: Altering tungsten, cobalt, and other carbide percentages tailors hardness, toughness and high-temperature strength. Ultra-fine grain grades offer the best toughness.
Geometry: Insert shape and size are designed based on application requirements, machinability, cutting forces, and heat dissipation needs. Chip breaker geometries improve chip control and cooling.
Tungsten carbide coatings: Proper coating material and thickness balance friction reduction with enough edge strength. Multilayer coatings combat wear through synergistic effects.
Surface finish: A smooth surface finish or textured patterns may be applied to further improve lubricity, heat transfer and chip flow.
Quality Control
Quality control plays a vital role in the manufacturing process of tungsten carbide inserts, ensuring that the final products meet the required specifications and deliver optimal performance. Various aspects of quality control are implemented throughout the manufacturing stages. These include:
（1）Raw Material Inspection
（2）Compaction Quality Check
（3）Pre-Sintering Examination
（4）Sintered Insert Inspection
（5）Machining Precision Verification
（6）Coating Quality Assessment
（7）Final Inspection and Packaging
By implementing comprehensive quality control measures at each manufacturing stage, tungsten carbide insert manufacturers can ensure consistent quality, reliability, and performance. These stringent processes help deliver inserts that meet or exceed customer expectations in terms of dimensional accuracy, hardness, wear resistance, and overall durability.
What is a tungsten carbide insert used for?
The tungsten carbide wear inserts are used to cut steel casing and plugs, remove down-hole junk and protect the surface of the downhole tools.
What is the composition of tungsten carbide inserts?
Carbide inserts are mainly made of solid carbide as the base and are finished through multiple production processes.
Can tungsten carbide inserts be used for cutting other materials besides metals?
Yes, tungsten carbide inserts can also be used for cutting some non-metallic materials besides metals: composites; stone; wood; plastics; ceramics
Are tungsten carbide inserts recyclable?
Yes, tungsten carbide inserts are recyclable. Tungsten carbide recycling is an important process that helps recover the valuable tungsten and carbide content from used or damaged inserts.
