Comparative Hardness Scales Steel
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The table below shows comparisons of various hardness scales. The information contained in the table is based on the assumption that the metal tested is homogeneous to a depth several times that of the indentation. The data shown in Data Set 1 is based upon extensive tests on carbon and alloy steels mostly in the heat-treated condition and is generally reliable on constructional alloy steel and tool steels in the as-forged, annealed, normalized, quenched and tempered conditions. These hardness comparisons are not as accurate in special cases such as high manganese steel, 18-8 stainless steel, and other austenitic steels, and nickel based alloys. The data shown in Data Set 2 are based upon the hardness measurements of unhardened steel, steel of soft temper, grey and malleable cast iron, and most non-ferrous metals and may not be as accurate for annealed metals of high Rockwell B hardness such as austenitic stainless steel, nickel, high nickel alloys, and aluminum.
| Brinell Hardness Number, 10mm Ball, 3000-kgf Load | Rockwell Hardness Number | Rockwell Superficial Hardness Number Superficial Diameter Penetrator | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Rockwell C-Scale Hardness Number | Diamond Pyramid Hardness Number Vickers | Standard Ball | Hultgren Ball | Tungsten Carbide Ball | A-Scale 60-kgf Load Diameter Penetrator | D-Scale 100-kgf Load Diameter Penetrator | 15-N Scale 15-kgf Load | 30-N Scale 30-kgf Load | 45-N Scale 45-kgf Load | Shore Scleroscope Hardness Number |
| Data Set 1 | ||||||||||
| 68 | 940 | - | - | - | 85.6 | 76.9 | 93.2 | 84.4 | 75.4 | 97 |
| 67 | 900 | - | - | - | 85.0 | 76.1 | 92.9 | 83.6 | 74.2 | 95 |
| 66 | 865 | - | - | - | 84.5 | 75.4 | 92.5 | 82.8 | 73.3 | 92 |
| 65 | 832 | - | - | 739 | 83.9 | 74.5 | 92.2 | 81.9 | 72.0 | 91 |
| 64 | 800 | - | - | 722 | 83.4 | 73.8 | 91.8 | 81.1 | 71.0 | 88 |
| 63 | 772 | - | - | 705 | 82.8 | 73.0 | 91.4 | 80.1 | 69.9 | 87 |
| 62 | 746 | - | - | 688 | 82.3 | 72.2 | 91.1 | 79.3 | 68.8 | 85 |
| 61 | 720 | - | - | 670 | 81.8 | 71.5 | 90.7 | 78.4 | 67.7 | 83 |
| 60 | 697 | - | 613 | 654 | 81.2 | 70.7 | 90.2 | 77.5 | 66.6 | 81 |
| 59 | 674 | - | 599 | 634 | 80.7 | 69.9 | 89.8 | 76.6 | 65.5 | 80 |
| 58 | 653 | - | 587 | 615 | 80.1 | 69.2 | 89.3 | 75.7 | 64.3 | 78 |
| 57 | 633 | - | 575 | 595 | 79.6 | 68.5 | 88.9 | 74.8 | 63.2 | 76 |
| 56 | 613 | - | 561 | 577 | 79.0 | 67.7 | 88.3 | 73.9 | 62.0 | 75 |
| 55 | 595 | - | 546 | 560 | 78.5 | 66.9 | 87.9 | 73.0 | 60.9 | 74 |
| 54 | 577 | - | 534 | 543 | 78.0 | 66.1 | 87.4 | 72.0 | 59.8 | 72 |
| 53 | 560 | - | 519 | 525 | 77.4 | 65.4 | 86.9 | 71.2 | 58.6 | 71 |
| 52 | 544 | 500 | 508 | 512 | 76.8 | 64.6 | 86.4 | 70.2 | 57.4 | 69 |
| 51 | 528 | 487 | 494 | 496 | 76.3 | 63.8 | 85.9 | 69.4 | 56.1 | 68 |
| 50 | 513 | 475 | 481 | 481 | 75.9 | 63.1 | 85.5 | 68.5 | 55.0 | 67 |
| 49 | 498 | 464 | 469 | 469 | 75.2 | 62.1 | 85.0 | 67.6 | 53.8 | 66 |
| 48 | 484 | 451 | 455 | 455 | 74.7 | 61.4 | 84.5 | 66.7 | 52.5 | 64 |
| 47 | 471 | 442 | 443 | 443 | 74.1 | 60.8 | 83.9 | 65.8 | 51.4 | 63 |
| 46 | 458 | 432 | 432 | 432 | 73.6 | 60.0 | 83.5 | 64.8 | 50.3 | 62 |
| 45 | 446 | 421 | 421 | 421 | 73.1 | 59.2 | 83.0 | 64.0 | 49.0 | 60 |
| 44 | 434 | 409 | 409 | 409 | 72.5 | 58.5 | 82.5 | 63.1 | 47.8 | 58 |
| 43 | 423 | 400 | 400 | 400 | 72.0 | 57.7 | 82.0 | 62.2 | 46.7 | 57 |
| 42 | 412 | 390 | 390 | 390 | 71.5 | 56.9 | 81.5 | 61.3 | 45.5 | 56 |
| 41 | 402 | 381 | 381 | 381 | 70.9 | 56.2 | 80.9 | 60.4 | 44.3 | 55 |
| 40 | 392 | 371 | 371 | 371 | 70.4 | 55.4 | 80.4 | 59.5 | 43.1 | 54 |
| 39 | 382 | 362 | 362 | 362 | 69.9 | 54.6 | 79.9 | 58.6 | 41.9 | 52 |
| 38 | 372 | 353 | 353 | 353 | 69.4 | 53.8 | 79.4 | 57.7 | 40.8 | 51 |
| 37 | 363 | 344 | 344 | 344 | 68.9 | 53.1 | 78.8 | 56.8 | 39.6 | 50 |
| 36 | 354 | 336 | 336 | 336 | 68.4 | 52.3 | 78.3 | 55.9 | 38.4 | 49 |
| 35 | 345 | 327 | 327 | 327 | 67.9 | 51.5 | 77.7 | 55.0 | 37.2 | 48 |
| 34 | 336 | 319 | 319 | 319 | 67.4 | 50.8 | 77.2 | 54.2 | 36.1 | 47 |
| 33 | 327 | 311 | 311 | 311 | 66.8 | 50.0 | 76.6 | 53.3 | 34.9 | 46 |
| 32 | 318 | 301 | 301 | 301 | 66.3 | 49.2 | 76.1 | 52.1 | 33.7 | 44 |
| 31 | 310 | 294 | 294 | 294 | 65.8 | 48.4 | 75.6 | 51.3 | 32.5 | 43 |
| 30 | 302 | 286 | 286 | 286 | 65.3 | 47.7 | 75.0 | 50.4 | 31.3 | 42 |
| 29 | 294 | 279 | 279 | 279 | 64.7 | 47.0 | 74.5 | 49.5 | 30.1 | 41 |
| 28 | 286 | 271 | 271 | 271 | 64.3 | 46.1 | 73.9 | 48.6 | 28.9 | 41 |
| 27 | 279 | 264 | 264 | 264 | 63.8 | 45.2 | 73.3 | 47.7 | 27.8 | 40 |
| Data Set 2 | ||||||||||
| 26 | 272 | 258 | 258 | 258 | 63.3 | 44.6 | 72.8 | 46.8 | 26.7 | 38 |
| 25 | 266 | 253 | 253 | 253 | 62.8 | 43.8 | 72.2 | 45.9 | 25.5 | 38 |
| 24 | 260 | 247 | 247 | 247 | 62.4 | 43.1 | 71.6 | 45.0 | 24.3 | 37 |
| 23 | 254 | 243 | 243 | 243 | 62.0 | 42.1 | 71.0 | 44.0 | 23.1 | 36 |
| 22 | 248 | 237 | 237 | 237 | 61.5 | 41.6 | 70.5 | 43.2 | 22.0 | 35 |
| 21 | 243 | 231 | 231 | 231 | 61.0 | 40.9 | 69.9 | 42.3 | 20.7 | 35 |
| 20 | 238 | 226 | 226 | 226 | 60.5 | 40.1 | 69.4 | 41.5 | 19.6 | 34 |
| (18) | 230 | 219 | 219 | 219 | - | - | - | - | - | 33 |
| (16) | 222 | 212 | 212 | 212 | - | - | - | - | - | 32 |
| (14) | 213 | 203 | 203 | 203 | - | - | - | - | - | 31 |
| (12) | 204 | 194 | 194 | 194 | - | - | - | - | - | 29 |
| (10) | 196 | 187 | 187 | 187 | - | - | - | - | - | 28 |
| (8) | 188 | 179 | 179 | 179 | - | - | - | - | - | 27 |
| (6) | 180 | 171 | 171 | 171 | - | - | - | - | - | 26 |
| (4) | 173 | 165 | 165 | 165 | - | - | - | - | - | 25 |
| (2) | 166 | 158 | 158 | 158 | - | - | - | - | - | 24 |
| (0) | 160 | 152 | 152 | 152 | - | - | - | - | - | 24 |