High-speed steel (HSS) is a type of tool steel known for its exceptional hardness, wear resistance, and ability to withstand high temperatures without losing its hardness. There are several types of high-speed steel, each with its own composition and properties tailored for specific applications. Here are some of the most common types:
M2 High-Speed Steel: M2 is perhaps the most widely used type of high-speed steel. It contains a high percentage of tungsten (around 6-7.5%), along with lesser amounts of other elements like molybdenum, chromium, vanadium, and carbon. M2 steel offers excellent wear resistance, toughness, and hardness, making it suitable for a wide range of cutting tools such as drills, taps, reamers, and milling cutters.
M35 High-Speed Steel: M35 is an improved version of M2 steel, with a higher cobalt content (around 5-8%). The addition of cobalt enhances the hot hardness and red hardness of the steel, making it particularly well-suited for high-speed cutting operations at elevated temperatures. M35 steel is commonly used for cutting tools in applications involving tough materials like stainless steel, nickel-based alloys, and titanium.
M42 High-Speed Steel: M42 is another cobalt-enhanced high-speed steel, with a cobalt content of around 8%. It offers superior heat resistance compared to M2 and M35, making it suitable for high-speed machining of difficult-to-cut materials such as superalloys, heat-resistant alloys, and stainless steels. M42 steel is often used in applications where high cutting speeds and prolonged tool life are critical.
T15 High-Speed Steel: T15 steel contains a high proportion of tungsten (around 12%) and smaller amounts of cobalt, vanadium, and chromium. It is known for its exceptional wear resistance, toughness, and heat resistance, even at extremely high cutting speeds. T15 steel is commonly used for high-performance cutting tools such as drills, end mills, and taps, particularly in applications involving high-speed machining of hardened steels and cast irons.
PM-HSS (Powder Metallurgy High-Speed Steel): PM-HSS is a type of high-speed steel produced using powder metallurgy techniques. It offers superior uniformity, finer grain structure, and improved mechanical properties compared to conventional high-speed steels. PM-HSS grades such as ASP23, ASP30, and ASP60 are designed for specific applications where exceptional wear resistance, toughness, and dimensional stability are required.
Each type of high-speed steel has its own unique combination of properties, making it suitable for different cutting tool applications. The choice of steel depends on factors such as the material being machined, cutting conditions, desired tool life, and cost considerations. By selecting the appropriate high-speed steel grade, manufacturers can optimize tool performance, improve productivity, and reduce machining costs.