High-Speed Steel (HSS) Drill Bits

High-speed steel (HSS) drill bits are made from tool steel alloys that maintain hardness at elevated temperatures. HSS bits are suitable for drilling wood, plastic, and soft metals at moderate speeds.

Material Composition

HSS typically contains tungsten, molybdenum, chromium, and vanadium in various proportions. M2 is the most common grade, offering a balance of toughness and wear resistance.

Temperature Resistance

HSS maintains its hardness at higher temperatures than carbon steel, allowing faster drilling speeds. However, excessive heat from high speeds or inadequate cooling will still damage the cutting edge.

Applications

HSS bits are general-purpose bits for drilling wood, plastic, aluminum, and mild steel. For harder materials or higher production rates, cobalt or carbide bits may be more appropriate.

Coatings

HSS bits are available with various coatings including titanium nitride (TiN), titanium aluminum nitride (TiAlN), and black oxide. Coatings can extend bit life and improve performance in specific materials.