Hardness conversion astm E 140 - 97
from	HV: Vickers Hardness HB: Brinell Hardness 10 mm C-ball 3000 kgf HK: Knoop Hardness 500 gf and over HRA: Rockwell A Hardness 60 kgf. HRB: Rockwell B Hardness 100 kgf. HRC: Rockwell C Hardness 150 kgf. HRD: Rockwell D Hardness 100 kgf. HR15N: Rockwell Superficial 15 kgf. HR30N: Rockwell Superficial 30 kgf. HR45N: Rockwell Superficial 45 kgf. HSc: Scleroscope Hardness
to	HV: Vickers Hardness HB: Brinell Hardness 10 mm C-Ball 3000 kgf HRC: Rockwell C Hardness 150 kgf.
1) Standard Hardness Conversion for metals acc. ASTM E 140 - 97, September 1999, Conversion for Non-Austenitic Steels, Table 1. The accuracy of the conversion depends on the accuracy of the provided data and the resulting curve-fits.
2) Indentation hardness is not a single fundamental property but a combination of properties, and varies with the type of test. The modulus of elasticity and the depth of indentation influence conversions. Therefore separate conversion tables are neccessary for different materials.
3) Brinell Hardness numbers in parentheses are outsite the range (HB>630) This limit is set to avoid errors introduced by the deformation of the ball indenter itself.
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