The major difference between Sandvik knife steels and 420HC is the microstructure. We allow a maximum carbide size of 2 microns in diameter. this is because in the razorblade industry they define "sharp" as a consitent edge radius of maximum 1 micro millimeter (about 0.00004" if my math is correct). This fine microstructure gives several advatages.
Toughness: Every particle in the steel is a "weak" point. Small carbides means small weak points and high toughness.
Sharpness: As described above.
Edge retention: Small carbides means many carbides. many carbides help with edge retention due to wear resistance.
Hardness: Small carbides dissolve easy, this means good reaction to heat treatment. Max HRC for 13C26 is 62 and for 12C27M it's 59.
Regrindability: Small carbide steel is easier to regrind than coarse steels.
Cost: I will not go into detail here since that is an agreement between Buck and Sandvik. But as a general statment you will find our product more expensive than standard AISI grades like 420 and 440. hopefully the benefits of productivity, easy of polishing and performance can fill the gap.
Regards
//Jerker
