Hardness Comparison Table

Brinell 3000kg load 10mm Ball Ø of Impression mm Hardness No. HB Diamond Pyramid No. (Vickers) HV Rockwell C. Scale 150kg Diamond Cone Rockwell B. Scaled 100kg 1/16 " Ball Equivalent Tensile Strength for Steel
N/mm² Tons/Sq. In.
2.05 899 - - - 3027 196
2.10 856 - - - 2888 187
2.15 817 - - - 2749 178
2.20 780 1150 70 - 2641 171
2.25 745 1050 68 - 2517 163
2.30 712 960 66 - 2409 156
2.35 682 885 64 - 2286 148
2.40 653 820 62 - 2193 142
2.45 627 765 60 - 2116 137
2.50 601 717 58 - 2023 131
2.55 578 675 57 - 1946 126
2.60 555 633 55 120 1869 121
2.65 534 598 53 119 1792 116
2.70 514 567 52 119 1730 112
2.75 495 540 50 117 1668 108
2.80 477 515 49 117 1606 104
2.85 461 494 47 116 1544 100
2.90 444 472 46 115 1498 97
2.95 429 454 45 115 1452 94
3.00 415 437 44 114 1405 91
3.05 401 420 42 113 1359 88
3.10 388 404 41 112 1297 84
3.15 375 389 40 112 1266 82
3.20 363 375 38 110 1220 79
3.25 352 363 37 110 1174 76
3.30 341 350 36 109 1143 74
3.35 331 339 35 109 1112 72
3.40 321 327 34 108 1081 70
3.45 311 316 33 108 1050 68
3.50 302 305 32 107 1019 66
3.55 293 296 31 106 988 64
3.60 285 287 30 105 958 62
3.65 277 279 29 104 927 60
3.70 269 270 28 104 911 59
3.75 262 263 26 103 880 57
3.80 255 256 25 102 849 55
3.85 248 248 24 102 834 54
3.90 241 241 23 100 803 52
3.95 235 235 22 99 788 51
4.00 229 229 21 98 772 50
4.05 223 223 20 97 757 49
4.10 217 217 18 96 726 47
4.15 212 212 17 96 710 46
4.20 207 207 16 95 695 45
4.25 201 202 15 94 680 44
4.30 197 197 13 93 664 43
4.35 192 192 12 92 649 42
4.40 187 187 10 91 633 41
4.45 183 183 9 90 618 40
4.50 179 179 8 89 610 39.5
4.55 174 174 7 88 602 39
4.60 170 170 6 87 595 38.5
4.65 167 166 4 86 587 38
4.70 163 163 3 85 579 37.5
4.75 159 159 2 84 564 36.5
4.80 156 156 1 83 556 36
4.85 152 153 0 82 541 35
4.90 149 149 -1 81 525 34
4.95 146 146 -2 80 517 33.5
5.00 143 143 -3 79 510 33
5.05 140 140 -4 78 494 32
5.10 137 137 -6 77 486 31.5
5.15 134 134 -7 76 479 31
5.20 131 131 -9 74 463 30
5.25 128 128 -11 73 456 29.5
5.30 126 126 -12 72 448 29
5.35 123 124 -14 71 440 28.5
5.40 121 121 -16 70 432 28
5.45 118 118 -17 69 417 27
5.50 116 116 -19 68 409 26.5
5.55 114 114 -20 67 402 26
5.60 111 112 - 66 394 25.5
5.65 109 109 - 65 386 25
5.70 107 107 - 64 378 24.5
5.75 105 105 - 62 371 24
5.80 103 103 - 61 363 23.5
5.85 101 101 - 60 355 23
5.90 99.2 99 - 59 351 22.75
5.95 97.3 97 - 57 347 22.5
6.00 95.5 95 - 56 340 22

The equivalents given are approximations and must not be accepted as rigid. Certain conditions, especially the incidence of cold work, can alter the relation between hardness and tensile strength profoundly.

The hardness systems, given above, are in general use in industry, and it is convenient to be able to translate the results of one in terms of the hardness units of the other.

The table is offered as a guide only, and should be used with due discretion.

Bright Bar Steel image

Further Resources