Hardness values and formulas Product information Hardness values | Formulas Material hardness value comparison table 1 Tensile Hardness Hardness Hardness Tensile Hardness Hardness Hardness strength Brinell Vickers Rockwell strength Brinell Vickers Rockwell   255 N/mm2   76 HB   80 HV — 1,155 N/mm2 342 HB 360 HV 36,6 HRC   285 N/mm2   85 HB   90 HV — 1,220 N/mm2 361 HB 380 HV 38,8 HRC   320 N/mm2   95 HB 100 HV — 1,290 N/mm2 380 HB 400 HV 40,8 HRC   350 N/mm2 105 HB 110 HV — 1,350 N/mm2 399 HB 420 HV 42,7 HRC   385 N/mm2 110 HB 120 HV — 1,420 N/mm2 418 HB 440 HV 44,5 HRC   415 N/mm2 124 HB 130 HV — 1,485 N/mm2 437 HB 460 HV 46,1 HRC   450 N/mm2 133 HB 140 HV — 1,555 N/mm2 456 HB 480 HV 47,7 HRC   480 N/mm2 143 HB 150 HV — 1,595 N/mm2 466 HB 490 HV 48,4 HRC   510 N/mm2 152 HB 160 HV — 1,665 N/mm2 485 HB 510 HV 49,8 HRC   545 N/mm2 162 HB 170 HV — 1,740 N/mm2 504 HB 530 HV 51,1 HRC   575 N/mm2 171 HB 180 HV — 1,810 N/mm2 523 HB 550 HV 52,3 HRC   610 N/mm2 181 HB 190 HV — 1,880 N/mm2 542 HB 570 HV 53,6 HRC   640 N/mm2 190 HB 200 HV — 1,955 N/mm2 561 HB 590 HV 54,7 HRC   675 N/mm2 199 HB 210 HV — 2,030 N/mm2 580 HB 610 HV 55,7 HRC   705 N/mm2 209 HB 220 HV — 3,105 N/mm2 599 HB 630 HV 56,8 HRC   740 N/mm2 219 HB 230 HV — 2,180 N/mm2 618 HB 650 HV 57,8 HRC   770 N/mm2 228 HB 240 HV 20,3 HRC — 636 HB 670 HV 58,8 HRC   800 N/mm2 238 HB 250 HV 22,2 HRC — — 690 HV 59,7 HRC   835 N/mm2 247 HB 260 HV 24,0 HRC — — 720 HV 61,0 HRC   865 N/mm2 257 HB 270 HV 25,6 HRC — — 760 HV 62,5 HRC   900 N/mm2 266 HB 280 HV 27,1 HRC — — 800 HV 64,0 HRC   930 N/mm2 276 HB 290 HV 28,5 HRC — — 840 HV 65,3 HRC   965 N/mm2 285 HB 300 HV 29,8 HRC — — 880 HV 66,4 HRC 1,030 N/mm2 304 HB 320 HV 32,2 HRC — — 920 HV 67,5 HRC 1,095 N/mm2 324 HB 340 HV 34,4 HRC — — — — Cutting speed m / min. Spindle speed U / min. Table feed mm / min. VC = p u dC u n1,000 n = VC u 1.000p u dC Vf = n u z u fZ VC = cutting speed m / min.The brands n= revolutions / min.dC = diameter mmof PRECITOOL n= Spindle speed / rotations min.Vf= Table feed mm / min.VC = cutting speed m / min.n= revolutions / min.dC = diameter mmz= number of teethfZ= feed mm / tooth Product information The brands of PRECITOOL Drilling tools Premium qualityfor serial production Top qualityfor the most demandinguser Industrial qualityfor the price-conscious a selected assortment with tools of the top class a cross-application an attuned assortment assortment with the highest in good quality and with the specialists in the quality and availability reasonable prices particular application www.precitool.de 15