Calculation Formulae Indentation Shape Notation Method 64 HRB W Ball material identifier (when a ball indenter is used). Steel ball indenter: S / Tungsten carbide indenter: W Hardness scale identifier (scale "B" in this case). Value of Rockwell hardness. Indentation Center-to-Center Distance Specimen-Edge to Indentation-Center Distance Thickness of Specimen or Plating Indentation center-to-center distance: 4d or more (has to be 2mm or more) Specimen-edge to indentation-center distance: 2.5d or more (has to be 1mm or more) Thickness Diamond indenter: 10h or more Ball indenter: 15h or more Rockwell scales A/C/D Rockwell scales B/E/F/G/H/K Rockwell Superficial scales N/T h = Permanent indentation depth (mm). h1 = Indentation depth produced by the preliminary test force. h2 = Indentation depth produced by the test force. h3 = Depth of indentation after unloading the test force. d = Indentation diameter. 002 . 0 100 h HR − = 002 . 0 130 h HR − = 001 . 0 100 h HR − = Hardness Conversion Table Rockwell Hardness Test Rockwell Hardness Test h h1 h3 h2 d 4d or more d 2.5d or more 10h or more (15h or more) h Calculation Formulae Indentation Shape Minimum Allowable Indentation Spacing Thickness of Specimen or Plating Indentation center-to-center distance: 3d or more Specimen-edge to indentation-center distance: 2.5d or more Thickness: 8h or more Brinell Hardness Test ) / 1 (1 2 2 2 D d D h − − = ) ( 2 0.102 2 2 d D D D F S F k HBW − − = = π h d 2 d1 Notation Method 600 HBW 1 / 30 / 20 Dwell time of the test force (20s). If not within the specified range (10s to 15s) Approximate kgf equivalent value of applied test force where (30 kgf = 294.2N). Diameter of the ball (mm). Referring to the material of the indenter. Steel indenter: S / Tungsten carbide indenter: W Hardness scale identifier (scale "B" in this case). Value of Brinell hardness. 3d or more d 2.5d or more 8h or more h Scale Indenter Test force (N) Application Diamond ** 147.1 294.2 441.3 147.1 294.2 441.3 147.1 294.2 441.3 147.1 294.2 441.3 147.1 294.2 441.3 15N 30N 45N 15T 30T 45T *15W *30W *45W *15X *30X *45X *15Y *30Y *45Y HR15N, HR30N, HR45N: Steels according to HRA, HRD and HRC for thin parts or thin hardened layers. HR15T, HR30T, HR45T: Soft steel and non-ferrous metals like HRF and HRB, in case of thin parts (e.g. deep-drawn sheet metal) HRA: Tungsten carbide and thin age-hardening steel or thinner surface layer than is HRC testable. Less stress and damage than with HRC. Tungsten carbide. HRB: Soft mild steel (sheet metal), non-ferrous metals. HRC: Tungsten carbide and age-hardening steel (tools, high-strength mild steel). HRD: Surface-hardened parts of average hardness. HRE: Cast iron, aluminum alloys, magnesium alloys, bearing metals. HRF: Cold rolled sheet metal, annealed bronze and copper. HRG: Phosphor bronze, beryllium copper, soft malleable cast iron. HRH: Aluminum, zinc, lead. HRK: Bearing metals and similar. Hardness Test Methods and Applications Calculation Formula k = Constant. F = Test force (N). S = Surface area of indentation. d = Arithmetic mean (mm) of the two diagonal length d1 and d2. θ = Angle between the opposite forces at the vertex of the pyramidal indenter (136°). h = Depth of indentation ( h = d/7). 2 2 2 2 F sin d F d S F HV = k = 0.1891 = 0.102 θ d1 d 2 h Indentation Shape Notation Method 640 HV 30 / 20 Duration time of the test force (20s). If not within the specified range (10s to 15s). Approximate kgf equivalent value of applied test force where (30 kgf = 294.2N). Hardness symbol. Value of Vickers hardness. Minimum Allowable Indentation Spacing Minimum Allowable Thickness of Specimen or Plating d d d 3d or more (6d or more) (3d or more) 3d or more (6d or more) 2.5d or more Indentation center-to-center distance Steel, nickel alloy, titanium alloy, copper and copper alloy: 3d or more Light alloys, lead, tin and alloys of the previously listed materials excluding titanium alloy: 6d or more When two neighboring indentations have different sizes, 'd' is taken to be that of the larger indentation. Specimen-edge to indentation-center distance Steel, nickel alloy, titanium alloy, copper and copper alloy: 2.5d or more. Light alloys, lead, tin and alloys of the previously listed materials excluding titanium alloy: 3d or more d 1.5d or more Thickness: 1.5d or more Vickers Hardness Test Relationship between Vickers Hardness and the Minimum Allowable Thickness of a Specimen 3000 30 1 150 100 2 1 15 0.3 750 60 5 0.0001 0.001 0.01 0.1 1 10 100 1000 10000 Brinell Rockwell Vickers Micro-Vickers Hardness Test Method Test force ( 10N) (Commonly known as "Nanoindentation" - specimen thickness: approx. 10μm or less) A relatively new method based on recording indenter force against penetration depth throughout the load-dwell-unload cycle, and calculating hardness and stiffness directly from this data. Distances and forces are very small and resolutions are in the nanometer and micronewton ranges. Instrumented Indentation Test (IIT) Integrity assessment of high-frequency quenching, flame quenching and welded parts. ■ Often-used range Macroscopic assessment from material to deeply-heat-treated objects Frequently used for various applications. Intensity assessment of metallic casting and foundry pieces. Standardized evaluation method of heat treatment including carburizing, decarburizing and nitriding. Frequently used for various applications including small parts and topical assessment. IIT 0.0005 0.05 Rockwell hardness Rockwell Superficial hardness Rockwell hardness Minimum thickness of specimen (mm) Minimum thickness of specimen (mm) Minimum thickness of specimen (mm) Rockwell Hardness Scales Relationship between Rockwell / RockwellSuperficial Hardness and the Minimum Thickness of a Specimen Rockwell Superficial Hardness Scales * Not part of ISO6508-1 ** Cone angle of the tip: 120°, Radius of curvature of the tip: 0.2mm Preliminary test force 98.07N Preliminary test force 29.42N Scale Indenter A D C F B G H E K *L *M *P *R *S *V Diamond ** Ball with a diameter of 1.5875mm Ball with a diameter of 6.35mm Ball with a diameter of 12.7mm Ball with a diameter of 3.175mm Ball with a diameter of 1.5875mm Ball with a diameter of 6.35mm Ball with a diameter of 12.7mm Ball with a diameter of 3.175mm Test force (N) Application 588.4 980.7 1471 588.4 980.7 1471 588.4 980.7 1471 588.4 980.7 1471 588.4 980.7 1471 ISO6508-1 JIS Z 2245 ISO6508-1 JIS Z 2245 ISO18265 (excerpted) ISO6507-1 JIS Z 2244 ISO6506-1 JIS Z 2243 ISO 6508-1 Rockwell Hardness Test -- Test Method ISO 6507-1 Vickers Hardness Test -- Test Method ISO 6506-1 Brinell Hardness Test --Test Method No.17006 500 1403 (1) c-(PA) KO Hardness Testing Special heat treatment, thin coating, surface- modification layer, elastic material, etc. (example: titanium system coating, DLC treatment, semiconductor-field material) k = Constant. F = Test force (N). S = Surface area of indentation. D = Diameter of the ball (mm). d = Arithmetic mean (mm) of the indentation diameters measured at 90° (d1, d2). h = Depth of indentation. HV=0.1891 t >1.5d h d/7 t: Thickness of specimen (mm) d: Diagonal length (mm) h: Depth of indentation (mm) [Example] Specimen thickness t: 0.15mm Specimen hardness: 185HV1 Test force F: 9.807N (1kgf) Diagonal length d: 0.1mm F d 2 d t h Vickers hardness HV 2000 1000 500 300 200 100 50 30 20 0.001 0.002 0.003 0.005 0.01 0.02 0.03 0.05 0.1 0.2 0.3 0.5 1 2 3 0.001 0.002 0.003 0.005 0.01 0.02 0.03 0.05 0.1 0.2 0.3 0.5 1 2 Minimum thickness of specimen t : mm Diagonal length of indentation d : mm 0.001 0.002 0.003 0.005 0.01 0.02 0.03 0.05 0.1 0.2 0.3 0.5 1 2 3 5 10 20 30 50 9.807×10 -3 19.61×10 -3 29.42×10 -3 49.03×10 -3 98.07×10 -3 0.1961 0.2942 0.4903 0.9807 1.961 2.942 4.903 9.807 19.61 29.42 49.03 98.07 196.1 294.2 490.3 Hardness symbol Test force F : N HV0.0005 4.903×10 -3 Table for unalloyed and low alloy steels and cast iron Tensile strength MPa Vickers hardness HV10 Brinell hardness HB Rockwell hardness HRB HRF HRC HRA HRD HR15N HR30N HR45N 575 180 171 87,1 107,2 610 190 181 89,5 108,7 640 200 190 91,5 110,1 675 210 199 93,5 111,3 705 220 209 95,0 112,4 740 230 219 96,7 113,4 770 240 228 98,1 114,3 20,3 60,7 40,3 69,6 41,7 19,9 800 250 238 99,5 115,1 22,2 61,6 41,7 70,6 43,4 22,2 835 260 247 (101) 24,0 62,4 43,1 71,6 45,0 24,3 865 270 257 (102) 25,6 63,1 44,3 72,6 46,4 26,2 900 280 266 (104) 27,1 63,8 45,3 73,4 47,8 27,9 930 290 276 (105) 28,5 64,5 46,5 74,2 49,0 29,5 965 300 285 29,8 65,2 47,5 74,9 50,2 31,1 995 310 295 31,0 65,8 48,4 75,6 51,3 32,5 1 030 320 304 32,2 66,4 49,4 76,2 52,3 33,9 1 060 330 314 33,3 67,0 50,2 76,8 53,6 35,2 1 095 340 323 34,4 67,6 51,1 77,4 54,4 36,5 1 125 350 333 35,5 68,1 51,9 78,0 55,4 37,8 1 155 360 342 36,6 68,7 52,8 78,6 56,4 39,1 1 190 370 352 37,7 69,2 53,6 79,2 57,4 40,4 1 220 380 361 38,8 69,8 54,4 79,8 58,4 41,7 1 255 390 371 39,8 70,3 55,3 80,3 59,3 42,9 1 290 400 380 40,8 70,8 56,0 80,8 60,2 44,1 1 320 410 390 41,8 71,4 56,8 81,4 61,1 45,3 1 350 420 399 42,7 71,8 57,5 81,8 61,9 46,4 1 385 430 409 43,6 72,3 58,2 82,3 62,7 47,4 1 420 440 418 44,5 72,8 58,8 82,8 63,5 48,4 1 455 450 428 45,3 73,3 59,4 83,2 64,3 49,4 1 485 460 437 46,1 73,6 60,1 83,6 64,9 50,4 1 520 470 447 46,9 74,1 60,7 83,9 65,7 51,3 1 555 480 456 47,7 74,5 61,3 84,3 66,4 52,2 1 595 490 466 48,4 74,9 61,6 84,7 67,1 53,1 1 630 500 475 49,1 75,3 62,2 85,0 67,7 53,9 1 665 510 485 49,8 75,7 62,9 85,4 68,3 54,7 1 700 520 494 50,5 76,1 63,5 85,7 69,0 55,6 1 740 530 504 51,1 76,4 63,9 86,0 69,5 56,2 1 775 540 513 51,7 76,7 64,4 86,3 70,0 57,0 1 810 550 523 52,3 77,0 64,8 86,6 70,5 57,8 1 845 560 532 53,0 77,4 65,4 86,9 71,2 58,6 1 880 570 542 53,6 77,8 65,8 87,2 71,7 59,3 1 920 580 551 54,1 78,0 66,2 87,5 72,1 59,9 1 955 590 561 54,7 78,4 66,7 87,8 72,7 60,5 1 995 600 570 55,2 78,6 67,0 88,0 73,2 61,2 2 030 610 580 55,7 78,9 67,5 88,2 73,7 61,7 2 070 620 589 56,3 79,2 67,9 88,5 74,2 62,4 2 105 630 599 56,8 79,5 68,3 88,8 74,6 63,0 2 145 640 608 57,3 79,8 68,7 89,0 75,1 63,5 2 180 650 618 57,8 80,0 69,0 89,2 75,5 64,1 660 58,3 80,3 69,4 89,5 75,9 64,7 670 58,8 80,6 69,8 89,7 76,4 65,3 680 59,2 80,8 70,1 89,8 76,8 65,7 690 59,7 81,1 70,5 90,1 77,2 66,2 700 60,1 81,3 70,8 90,3 77,6 66,7 720 61,0 81,8 71,5 90,7 78,4 67,7 740 61,8 82,2 72,1 91,0 79,1 68,6 760 62,5 82,6 72,6 91,2 79,7 69,4 780 63,3 83,0 73,3 91,5 80,4 70,2 800 64,0 83,4 73,8 91,8 81,1 71,0 820 64,7 83,8 74,3 92,1 81,7 71,8 840 65,3 84,1 74,8 92,3 82,2 72,2 860 65,9 84,4 75,3 92,5 82,7 73,1 880 66,4 84,7 75,7 92,7 83,1 73,6 900 67,0 85,0 76,1 92,9 83,6 74,2 920 67,5 85,3 76,5 93,0 84,0 74,8 940 68,0 85,6 76,9 93,2 84,4 75,4 • Brinell hardness values up to 450 HB were determined using a steel ball indenter, those above this value were determined with a hardmetal ball. Table for Cartridge brass (70 % Copper 30 % Zinc Alloy) HV 30 Rockwell Hardness Number HB HRB HRF HR15T HR30T HR45T HBS10/500 196 93,5 110,0 90,0 77,5 66,0 169 194 — 109,5 — — 65,5 167 192 93,0 — — 77,0 65,0 166 190 92,5 109,0 — 76,5 64,5 164 188 92,0 — 89,5 — 64,0 162 186 91,5 108,5 — 76,0 63,5 161 184 91,0 — — 75,5 63,0 159 182 90,5 108,0 89,0 — 62,5 157 180 90,0 107,5 — 74,5 62,0 156 178 89,0 — — — 61,5 154 176 88,5 107,0 — — 61,0 152 174 88,0 — 88,5 74,0 60,5 150 172 87,5 106,5 — 73,5 60,0 149 170 87,0 — — — 59,5 147 168 86,0 106,0 88,0 73,0 59,0 146 166 85,5 — — 72,5 58,5 144 164 85,0 105,5 — 72,0 58,0 142 162 84,0 105,0 87,5 — 57,5 141 160 83,5 — — 71,5 56,5 139 158 83,0 104,5 — 71,0 56,0 138 156 82,0 104,0 87,0 70,5 55,5 136 154 81,5 103,5 — 70,0 54,5 135 152 80,5 103,0 — — 54,0 133 150 80,0 — 86,5 69,5 53,5 131 148 79,0 102,5 — 69,0 53,0 129 146 78,0 102,0 — 68,5 52,5 128 144 77,5 101,5 86,0 68,0 51,5 126 142 77,0 101,0 — 67,5 51,0 124 140 76,0 100,5 85,5 67,0 50,0 122 138 75,0 100,0 — 66,5 49,0 121 136 74,5 99,5 85,0 66,0 48,0 120 134 73,5 99,0 — 65,5 47,5 118 132 73,0 98,5 84,5 65,0 46,5 116 130 72,0 98,0 84,0 64,5 45,5 114 128 71,0 97,5 — 63,5 45,0 113 126 70,0 97,0 83,5 63,0 44,0 112 124 69,0 96,5 — 62,5 43,0 110 122 68,0 96,0 83,0 62,0 42,0 108 120 67,0 95,5 — 61,0 41,0 106 118 66,0 95,0 82,5 60,5 40,0 105 116 65,0 94,5 82,0 60,0 39,0 103 114 64,0 94,0 81,5 59,5 38,0 101 112 63,0 93,0 81,0 58,5 37,0 99 110 62,0 92,6 80,5 58,0 35,5 97 108 61,0 92,0 — 57,0 34,5 95 106 59,5 91,2 80,0 56,0 33,0 94 104 58,0 90,5 79,5 55,0 32,0 92 102 57,0 89,8 79,0 54,5 30,5 90 100 56,0 89,0 78,5 53,5 29,5 88 98 54,0 88,0 78,0 52,5 28,0 86 96 53,0 87,2 77,5 51,5 26,5 85 94 51,0 86,3 77,0 50,5 24,5 83 92 49,5 85,4 76,5 49,0 23,0 82 90 47,5 84,4 75,5 48,0 21,0 80 88 46,0 83,5 75,0 47,0 19,0 79 86 44,0 82,3 74,5 45,5 17,0 77 84 42,0 81,2 73,5 44,0 14,5 76 82 40,0 80,0 73,0 43,0 12,5 74 80 37,5 78,6 72,0 41,0 10,0 72