CNC tools are cutting tools that are used on CNC machines to perform various machining operations, such as milling, drilling, turning, and threading. CNC tools are made of different materials that have different properties and applications. Two of the most common materials for CNC tools are high-speed steel (HSS) and tungsten steel (also known as hard alloy or cemented carbide).
What are the main differences between these two materials and how do they affect the performance and quality of your CNC machining? In this article, we will compare and contrast HSS and tungsten steel CNC tools in terms of their composition, characteristics, advantages, disadvantages, and applications.
Composition
HSS is a type of tool steel that contains alloying elements such as tungsten, molybdenum, chromium, vanadium, and cobalt. The total amount of alloying elements makes up around 10-25% of the steel. HSS is also known as “white steel” because of its sharpness.
Tungsten steel is a type of composite material that consists of at least one metal carbide (usually tungsten carbide) and a metal binder (usually cobalt or nickel). The carbide component accounts for 99% of the material, while the binder component accounts for 1%. Tungsten steel is also known as “hard alloy” or “cemented carbide” because of its hardness.
Characteristics
HSS has high hardness, wear resistance, and heat resistance. It can be hardened even when cooled in air during the quenching process. It can maintain high hardness even under high heat generated by high-speed cutting (around 500°C), resulting in a hardness of over 60 on the Rockwell scale (HRC). HSS is also flexible and can handle more impact and shock than carbide.
Tungsten steel has higher hardness, wear resistance, strength, toughness, heat resistance, and corrosion resistance than HSS. It can achieve high speeds and feeds on various materials. It can also reduce friction and prevent built-up edge formation. It can maintain high hardness even at 1000°C. However, tungsten steel is also brittle and expensive, and it requires special cutting conditions and coolant systems.
Advantages
HSS has the following advantages:
It is cheaper than tungsten steel
It can be sharpened easily and reused
It can handle more impact and shock than tungsten steel
It can be used for low-speed operations on various materials
Tungsten steel has the following advantages:
It has higher hardness and wear resistance than HSS
It can achieve higher speeds and feeds than HSS
It can produce finer finishes and accurate dimensions on various materials
It can reduce friction and heat generation on the workpiece
It has higher corrosion resistance than HSS
Disadvantages
HSS has the following disadvantages:
It has lower wear resistance and heat resistance than tungsten steel
It cannot operate at very high speeds or temperatures
It may lose its sharpness quickly when cutting hard or abrasive materials
It may generate more heat and friction on the workpiece
Tungsten steel has the following disadvantages:
It is more expensive than HSS
It is brittle and prone to chipping or breaking if subjected to excessive force or vibration
It requires special cutting conditions and coolant systems
It may cause more tool wear when cutting soft or ductile materials
Applications
HSS is mainly used for making complex, thin-edged, and impact-resistant cutting tools, such as turning tools, drills, hobs, machine blades, and demanding dies. HSS is suitable for general-purpose machining of various materials, especially ferrous metals.
Tungsten steel is mainly used for making high-performance cutting tools that require high speed, precision, and quality, such as end mills, reamers, taps, dies, inserts, cutters, etc. Tungsten steel is suitable for machining hard materials such as cast iron, hardened steels, and superalloys.
Conclusion
HSS and tungsten steel are two different materials for CNC tools that have different advantages and disadvantages. HSS is cheaper, more flexible, and more impact-resistant than tungsten steel, but it has lower wear resistance and heat resistance. Tungsten steel is harder, more wear-resistant, and more heat-resistant than HSS, but it is more expensive, more brittle, and more demanding on cutting conditions.
Depending on your budget, quality requirements, and machining conditions, you can choose the most suitable material for your CNC tools.
We hope this article has been helpful to you. If you have any questions or comments, please feel free to contact us.
