Approximate Conversion Table o f Hardness

Approximate conversion value for Brinell hardness. (The source: JIS HB Ferrous Materials and Metallurgy I -2005) *1

Brinell,HB 10mm ballHV ,Rockwell 3HSApprox.Brinell,HB 10mm ball,HVRockwell 3HSApprox.
Loa3000kgrsHRAHRBHRCHRDetensileLoa3000kgrsHRAHRBHRCHRDetensile
ard lTunstenickeA Scale,B Scale, Load 100kg,C Scale, LoadD Scale, Loadhorstrength (MPa)ard lTunstenickeA Scale,B Scale, Load 100kg,C Scale, LoadD Scale, Loadhorstrength (MPa)
tand balg carbide ballVLoad 60kg, Brale DidDiameter 1/16 in.150kg, brale100kg, BraleS2tand balg carbide ballVoad 60kg, Brale DidDiameter 1/16 in.150kg, brale100kg, BraleS2
SamonSteel balldiamondDiamondSamonSteel balldiamondDiamond
−−94085.6−68.076.997−42942945573.4−45.759.7611510
−−92085.3−67.576.596−41541544072.8−44.558.8591460
−−90085.0−67.076.195−40140142572.0−43.157.8581390
−(767)88084.7−66.475.793−38838841071.4−41.856.8561330
−(757)86084.4−65.975.392−37537539670.6−40.455.7541270
−(745)84084.1−65.374.891−36336338370.0−39.154.6521220
−(733)82083.8−64.774.390−35235237269.3(110.0)37.953.8511180
−(722)80083.4−64.073.888−34134136068.7(109.0)36.652.8501130
−(712)−−−−−−−33133135068.1(108.5)35.551.9481095
−(710)78083.0−63.373.387−32132133967.5(108.0)34.351.0471060
−(698)760826−62572686−
...31131132866.9(107.5)33.150.0461025
−(684)74082.2−61.872.1−−30230231966.3(107.0)32.149.3451005
−(682)73782.2−61.772.084−29329330965.7(106.0)30.948.343970
−(670)72081.8−61.071.583−28528530165.3(105.5)29.947.6−950
−(656)70081.3−60.170.8−−27727729264.6(104.5)28.846.741925
−(653)697812−60070781−
...26926928464.1(104.0)27.645.940895
−(647)69081.1−59.770.5−−26226227663.6(103.0)26.645.039875
−(638)680808−59270180−255255269630(1020)25444238850
−630670. 80.6−. 58.8. 69.8−−248248261. 62.5. (101.0). 24.2. 43.237825
−62766780.5−58.769.779−24124125361.8100.022.842.036800
−−67780.7−59.170.0−−23523524761.499.021.741.435785
−60164079.8−57.368.777−22922924160.898.220.540.534765
223223234−973(188)−−−
−−64079.8−57.368.7−−217217228−. 96.4. (17.5)−33725
−57861579.1−56.067.775−212212222−95.5(16.0)−−705
−−60778.8−55.667.4−−207207218−94.6(15.2)−32690
−55559178.4−54.766.7732055201201212−93.8(13.8)−31675
197197207−92.8(12.7)−30655
−−57978.0−54.066.1−2015192192202−91.9(11.5)−29640
−53456977.8−53.565.8711985187187196−90.7(10.0)−−620
−−55377.1−52.565.0−1915183183192−90.0(9.0)−28615
−51454776.9−52.164.7701890179179188−89.0(8.0)−27600
174174182−87.8(64)−−585
(495)−53976.7−51.664.3−1855170170178−86.8. (5.4)−26570
−−53076.4−51.163.9−1825167167175−86.0(4.4)−−560
−49552876.3−51.063.8681820
163163171−85.0(3.3)−25545
1795036316156163829525
(477) −− −56 5085. 75.6− −. 49.6.2 627− −1780 17405 149149156− −. 80.8(0.9) −− −− 23505
−47750875.6−49.6. 62.7661740143143150−78.7−−22490
137137143−76.4−−21460
(461)−49575.1−48.8619−1680
−−49174.9−48.5. 61.7−1670131131137−74.0−−−450
485121327204
−46149174.9−.61.76516701266−.−−2035
121121127−69.8−−19415
444−47474.3−47.261.0−1595116116122−67.6−−18400
− −− 444472 47274.2 74.2− −47.1 47.160.8 60.8− 631585 1585111111117−65.7−−15385

Note : *1: This table is based on AMS Metals Handbook, the 8th Edition, Volume 1, and includes some information added to “Approx. tensile strength (MPa),” such as the values calculated in metric; and Brinell hardness that exceeds recommended values. *2: 1 MPa = 1 N/mm2 *3: Figures in ( ) are not commonly used. It’s just reference.