TourBrinell hardness HBW [kfg/cm2]

 Brinell Hardness / plastic deformation

 Load F kN
 Ball diameter D mm
 Diameter of indentation d/D (range between 0.24 and 0.6) -
 Contact area A mm2
 Indentation δ mm
 Brinell Hardness1 / Mean contact pressure pm MPa

 Elastic Deformation / Hertz

 Young's modulus E GPa  GPa
 Poisson's ratio ν
 Ball diameter D mm
 Mean contact pressure pmc = Rp0.2 MPa 
 Effective Young's modulus E' GPa
 Effective contact radius R' 10-3 m
 Initial contact diameter d = 2r 10-3 m
 Indentation δ 10-6 m
 Contact load Fc N
1HBW300 = 300 kgf/cm2 = 3000 MPa