Hardness Conversion Table Brinell Hardness Rockwell Hardness Steel Tungsten Carbide Ball 3000 kg A Scale 60 kg B Scale 100 kg C Scale 150 kg Tensile Stength (approx.) PSI - 86 - 68 - - 85 - 68 - - 85 - 67 - 767 85 - 66 - 757 84 - 66 - 745 84 - 65 - 733 84 - 65 - 722 83 - 64 - 712 - - - - 710 83 - 63 - 698 83 - 62 - 684 82 - 62 - 682 82 - 62 - 670 82 - 61 - 656 81 - 60 - 653 81 - 60 - 647 81 - 60 - 638 81 - 59 329,000 630 81 - 59 324,000 627 80 - 59 323,000 601 80 - 57 309,000 578 79 - 56 297,000 555 78 - 55 285,000 534 78 - 54 274,000 514 77 - 52 263,000 495 76 - 51 253,000 477 76 - 50 243,000 461 75 - 48 235,000 444 74 - 47 225,000 429 73 - 46 217,000 415 73 - 44 210,000 401 72 - 43 202,000 388 71 - 42 195,000 375 71 - 40 188,000 363 70 - 39 182,000 352 69 - 38 176,000 341 69 - 37 170,000 331 68 - 36 166,000 321 68 - 34 160,000 311 67 - 33 155,000 302 66 - 32 150,000 293 66 - 31 145,000 285 65 - 30 141,000 277 65 - 29 137,000 269 64 - 28 133,000 262 64 - 27 129,000 255 63 - 25 126,000 248 62 - 24 122,000 241 62 100 23 118,000 235 61 99 22 115,000 229 61 98 20 111,000 223 - 97 20 - 217 - 96 18 105,000 212 - 96 17 102,000 207 - 95 16 100,000 201 - 94 15 98,000 197 - 93 - 95,000 192 - 92 - 93,000 187 - 91 - 90,000 183 - 90 - 89,000 179 - 89 - 87,000 174 - 88 - 85,000 170 - 87 - 83,000 167 - 86 - 81,000 163 - 85 - 79,000 156 - 83 - 76,000 149 - 81 - 73,000 143 - 79 - 71,000 137 - 76 - 67,000 131 - 74 - 65,000 126 - 72 - 63,000 121 - 70 - 60,000 116 - 68 - 58,000 111 - 66 - 56,000