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HSS Twist Drill Bits Fully Ground for Metal

HSS Twist Drill Bits Fully Ground for Metal

This HSS Twist Drill Bits Fully Ground for Metal is manufactured from premium high-speed steel (HSS4341/M2/M35 grade), achieving an overall hardness of HRC 62-65. The M35 grade incorporates 5% cobalt, significantly enhancing hardness, wear resistance, and red hardness. The M2 grade offers a cost-effective advantage while maintaining reliable basic cutting performance. The entire drill body undergoes integrated heat treatment (quenching and multiple tempering), ensuring uniform hardness distribution for a sharp cutting edge combined with appropriate toughness.   The drill point features a standard 118° angle (a 135° split-point option is available for hard materials), paired with a 30° helix angle and an 8° clearance angle. The cutting edge is precision ground and honed for exceptional sharpness and reduced resistance, enabling stable engagement and smooth, burr-free drilling from the initial stage. The chisel edge is properly thinned to lower axial force and improve centering accuracy.…