The Ultimate Guide to Metal Hardness (with Chart)

Are you curious about the hardness of metals and minerals?

Do you want to learn more about the different types of hardness tests and how they are used to measure a material’s resistance to deformation?

Look no further than this comprehensive guide on metal hardness from MachineMfg.

From scratch hardness testing to rebound hardness testing, this article covers all the different methods used to evaluate the hardness of metals and minerals.

You’ll learn about the various types of indentation hardness tests, including Brinell hardness, Rockwell hardness, Vickers hardness, and micro-hardness, and how they differ in terms of the indenter used, the applied load, and the duration of the load.

In addition to detailed explanations of the different hardness tests, this article also includes a handy chart of non-ferrous metal hardness, with information on tensile strength, Rockwell surface, Vickers, Brinell, and more.

Whether you’re a materials scientist, engineer, or just someone with a general interest in the properties of metals and minerals, this article is a must-read.

So dive in and discover everything you need to know about metal hardness!

What Is Metal Hardness?

Hardness is a metric that measures a material’s resistance to local deformations, such as plastic deformation, indentations, or scratches.

It is a crucial factor in determining the hardness of a material.

Types of Metal Hardness

According to the different test methods, there are three types of hardness.

① Scratch hardness

Hardness is primarily utilized to compare the resistance to local deformation of various minerals.

The process involves using a rod with a hard and soft end to test the material by sliding it along the rod.

The material’s softness or hardness is determined based on the length of the scratch it leaves on the rod.

Typically, scratches made by harder materials are longer and those made by softer materials are shorter.

② Indentation hardness

Indentation hardness testing is primarily used to evaluate metal materials. It involves applying a specified indenter to the surface of the material under test with a specific load.

The material’s hardness is determined by comparing the amount of local plastic deformation on the material’s surface.

There are several types of indentation hardness tests, including Brinell hardness, Rockwell hardness, Vickers hardness, and micro-hardness, which differ in terms of the indenter used, the applied load, and the duration of the load.

③ Rebound hardness

Rebound hardness testing is primarily used for metal materials. The method involves using a special small hammer that is dropped from a specific height to impact the material sample being tested.

The material’s hardness is determined by the amount of strain energy stored in and then released from the sample during the impact, which is measured by the rebound height of the hammer.

Metal Hardness Chart

Metals Mohs Hardness Chart

The Mohs hardness is a standard for representing mineral hardness, first proposed in 1822 by German mineralogist Frederich Mohs. It is a standard used in mineralogy or gemology. Mohs hardness is determined by using a diamond pyramid needle to scratch the surface of the tested mineral and measure the depth of the scratch. The depth of this scratch is the Mohs hardness, represented by the symbol HM. It is also used to indicate the hardness of other materials.

The depth of the measured scratch is divided into ten levels to represent hardness (scratch method): talc 1 (smallest hardness), gypsum 2, calcite 3, fluorite 4, apatite 5, orthoclase (feldspar) 6, quartz 7, topaz 8, corundum 9, diamond 10. The hardness of the tested mineral is determined by comparing scratches with the standard minerals in the Mohs hardness tester. Although the measurement of this method is rough, it is convenient and practical. It is often used to measure the hardness of natural minerals.

Hardness values are not absolute hardness values, but values represented in order of hardness.

See also  Palladium Weight Calculator

When applying, compare the hardness by scratching. For example, if a mineral can scratch calcite but not fluorite, its Mohs hardness is 3 to 4, and others are inferred. Mohs hardness is only relative hardness, which is rough. The hardness of talc is 1, diamond is 10, and corundum is 9, but the absolute hardness measured by a microhardness tester is 4192 times that of talc for diamond, and 442 times that of talc for corundum. Mohs hardness is convenient to use and is often used in field operations. For example, the hardness of fingernails is about 2.5, copper coins are 3.5-4, steel knives are 5.5, and glass is 6.5.

In addition to the original list of 1 to 10 kinds of minerals, the hardness values of common metals are listed here for reference.

MetalElementHardness (Mohs)
Carbon(diamond)C10
BoronB9.3
Titanium CarbideTi+C9
Tungsten CarbideW+C9
ChromiumCr8.5
TungstenW7.5
VanadiumV7
RheniumRe7
OsmiumOs7
SiliconSi6.5
RutheniumRu6.5
TantalumTa6.5
IridiumIr6.5
TitaniumTi6
ManganeseMn6
GermaniumGe6
NiobiumNb6
RhodiumRh6
UraniumU6
BerylliumBe6
MolybdenumMo5.5
HafniumHf5.5
CobaltCo5
ZirconiumZr5
PalladiumPd4.75
White GoldAu+Ni+Pd4
SteelFe+C4
IronFe4
NickelNi4
ArsenicAs3.5
PlatinumPt3.5
BrassCu+Zn3
BronzeCu+Sn3
CopperCu3
AntimonySb3
ThoriumTh3
AluminumAl2.75
MagnesiumMg2.5
ZincZn2.5
SilverAg2.5
LanthanumLa2.5
CeriumCe2.5
GoldAu2.5
TelluriumTe2.25
BismuthBi2.25
CadmiumCd2
CalciumCa1.75
GalliumGa1.5
StrontiumSr1.5
TinSn1.5
MercuryHg1.5
LeadPb1.5
BariumBa1.25
IndiumIn1.2
ThalliumTi1.2
LithiumLi1.2
SodiumNa0.5
PotassiumK0.4
RubidiumRb0.3
CaesiumCs0.2

Common Metal Material Hardness Chart

No.Material CodeStrength GradeHardness Value(HB)
011Cr13440(45)197~229
355187~229
021Cr12Mo550229~255
450197~229
03Cr11MoV490(50)217~248
390192~241
590235~269
04Cr12WMoV590235~269
690269~302
052Cr12NiMoWV760293~331
06ZG20CrMoV310140~201
0725Cr2MoVA590241~277
735269~302
0830Cr2MoV440179~229
590241~277
735269~302
0938CrMoAl590241~277
685277~302
785293~321
10A3Hardness after Nitriding Component Normalizing<131
1115#<143
1225#<170
13ZG25<170
1420CrA<179
1512CrNi3A<252
162Cr13490217~248
590235~269
172Cr12NiW1Mo1V735285~302
180Cr17Ni4Cu4Nb590262~302
760277~311
19Cr5Mo/248~302
20GH132(GBn181-82)/284~349
21GH136(GBn181-82)/298~390
22R-26550262~331
233Cr13590235~269
685269~302
233Cr13785286~321
241Cr18Ni9Ti205(225)≦187
250Cr18Ni9205≦187
261Cr18Ni9205≦187
27Cr15Ni3Bw3Ti390207~255
2834CrMo1A490(590)/
2930Cr2MoV590241~277
690256~287
735269~302
3034CrNi3Mo590220~260
690240~282
735255~284
785271~298
3130Cr2Ni4MoV550207~262
690241~302
760262~321
830285~341
3215CrMoA245131~163
490207~241
3315Cr1Mo275≦207
3412Cr1MoVA245131~163
3512Cr2Mo1275≦197
315≦207
3615Cr1Mo1VA325146~196
3725#235(215)110~170
3830#265≦187
3935#265156~217
255140~187
235121~187
4045#295162~217
285149~217
440197~229
345217~255
4115CrMoA245131~163
490207~241
4220MnMo350149~217
4340CrNi3MoA550207~262
690241~302
4415CrMoA490207~241
4540CrA390192~223
4540CrA490217~235
590241~277
685269~302
4640CrNi2MoA540207~269
640248~277
785269~321
4735CrMoA490217~255
590241~277
4840CrNiMoA690255~293
4920Cr1Mo1VtiB690255~293
5030Cr1Mo1V590241~277
5130Cr1Mo1V690255~285

Hardness Conversion Table for Common Metals (such as Carbon Steel, Alloy Steel, etc.)

Rockwell hardnessSurface Rockwell hardnessVickersBrinellShore
HRAHRBHRCHRD15N30N45NHVHBHS
60kgf100kgf150kgf100kgf15kgf30kgf45kgf50kgf3000kgfJIS
85.6 6876.993.284.475.4940 97.6
85.3 67.576.5938474.3920 96.4
85 6776.192.983.674.2900 95.2
84.7 66.575.792.783.173.6880 94
84.4 65.975.392.582.773.1860 92.8
84.1 65.374.892.382.272.2840 91.5
83.8 64.774.392.181.771.8820 90.2
83.4 6473.891.881.171800 88.9
83 63.373.391.580.470.2780 87.5
82.6 62.572.691.279.769.4760 86.2
82.2 61.872.19179.168.6740 84.8
81.8 6171.590.778.467.7720 83.3
81.3 60.170.890.377.666.7700 81.8
81.1 59.770.590.177.266.2690 81.1
80.8 59.270.189.876.865.7680 80.3
80.6 58.869.889.776.465.3670 79.6
80.3 58.369.489.575.964.7660 78.8
80 57.86989.275.564.1650 78
79.8 57.368.78975.163.5640 77.2
79.5 56.868.388.874.663630 76.4
79.2 56.367.988.574.262.4620 75.6
78.9 55.767.588.273.661.7610 74.7
78.6 55.2678873.261.2600 73.9
78.4 54.766.787.872.760.5590 73.1
78 54.166.287.572.159.9580 72.2
77.8 53.665.887.271.759.3570 71.3
77.4 5365.486.971.258.6560 70.4
77 52.364.886.670.557.855050569.6
76.7 51.764.486.3705754049668.7
76.4 51.163.98669.556.253048867.7
76.1 50.563.585.76955.652048066.8
75.7 49.862.985.468.354.751047365.9
75.3 49.162.28567.753.950046564.9
74.9 48.461.684.767.153.149045664
74.5 47.761.384.366.452.248044863
74.1 46.960.783.965.751.347044162
73.6 46.160.183.664.950.446043361
73.3 45.359.483.264.349.445042560
72.8 44.558.882.863.548.444041559
72.3 43.658.282.362.747.443040558
71.8 42.757.581.861.946.442039756.9
71.4 41.856.881.461.145.341038855.9
70.8 40.8658160.244.140037954.8
70.3 39.855.280.359.342.939036953.7
69.811038.854.479.858.441.738036052.6
69.2 37.753.679.257.440.437035051.5
68.710936.652.878.656.439.136034150.4
68.1 35.551.97855.437.835033149.3
67.610834.451.177.454.436.534032248.1
67 33.350.276.853.635.233031347
66.410732.249.476.252.333.932030345.8
65.8 31.648.475.851.832.831029444.6
65.2105.529.847.574.950.231.130028443.4
64.8 29.247.174.649.730.429528042.8
64.5104.528.546.574.24929.529027542.2
64.2 27.84673.848.428.728527041.6
63.8103.527.145.373.447.827.928026540.9
63.5 26.444.97347.227.127526140.3
63.110225.644.372.646.426.227025639.7
62.7 24.843.772.145.725.226525239
62.41012443.171.64524.326024738.4
62 23.142.271.144.223.225524337.8
61.699.522.241.770.643.422.225023837.2
61.2 21.341.170.142.521.124523336.5
60.798.120.340.369.641.719.924022835.9
 96.718    23021934.1
 9515.7    22020933.2
 93.413.4    21020031.8
 91.511    20019030.4
 89.58.5    19018129
 87.16    18017127.7
 853    17016226.5
 81.70    16015225
 78.7     15014323.7
 78     14013322.1
 71.2     13012420.6
 66.7     12011419.1
 62.3     11010517.6
 56.2     1009516.1

Hardness Conversion Table for Soft Metals (such as Copper and Aluminum)

Rockwell hardnessSurface Rockwell hardnessVickers hardness
HRBHRF15T30T45THV
100kgf60kgf15kgf30kgf45kgf50kgf
93.51109077.566196
 109.5  65.5194
93  7765192
92.5109 76.564.5190
92 89.5 64188
91.5108.5 7663.5186
91  75.563184
90.510889 62.5182
90107.5 7562180
89  74.561.5178
88.5107  61176
88 88.57460.5174
87.5106.5 73.560172
87   59.5170
86106887359168
85.5  72.558.5166
85105.5 7258164
8410587.5 57.5162
83.5  71.556.7160
83104.5 7156158
821048770.555.5156
81.5103.5 7054.5154
80.5103  54152
80 86.569.553.5150
79102.5 6953148
78102 68.552.5146
77.5101.5866851.5144
77101 67.551142
76100.585.56750140
75100 66.549138
74.599.5856648136
73.599 65.547.5134
7398.584.56546.5132
72988464.545.5130
7197.5 63.545128
709783.56344126
6996.5 62.543124
6896836242122
6795.5 6141120
669582.560.540118
6594.5826039116
649481.559.538114
63938158.537112
6292.680.55835.5110
6192 5734.5108
59.591.2805633106
5890.579.55532104
5789.87954.530.5102
568978.553.529.5100
54887852.52898
5387.277.551.526.596
61.686.67750.524.594
49.585.476.5492392
47.584.475.5482190
4683.575471988
4482.374.545.51786
4281.273.54414.584
4080734312.582
37.578.672411080
3577.471.539.57.578
32.57670.5384.576
3074.87036174
27.573.26934 72
24.571.66832 70
21.5706730 68
18.568.56628 66
15.566.86525.5 64
12.56563.523 62
106362.520.5 60
 616118 58
 58.86015 56
 56.558.512 54
 53.557  52
 50.555.5  50
 4954.5  49
 4753.5  48
 45   47
 43   46
 40   45

Hardness of Metal Materials Used in Power Stations

MaterialsReference Standards and Requirements(HB)Control Scope(HB)Note
210CASTM A210,≤179130~179 
T1a, 20MoG, STBA12, 15Mo3ASTM A209,≤153125~153 
T2, T11, T12, T21, T22, 10CrMo910ASTM A213,≤163120~163 
P2, P11, P12, /P21, P22, 10CrMo910 125~179 
P2, P11, P12, /P21P22, 10CrMo910 type pipe fittings 130~197The lower limit of the weld seam must not be less than that of the base material,upper limit≤241
T23ASTM A213,≤220150~220 
12Cr2MoWVTiB(G102) 150~220 
T24ASTM A213,≤250180~250 
T/P91, T/P92, T911, T/P122ASTM A213,≤250ASTM A335,≤250180~250The hardness of “P” type pipes refers to that of “T” type pipes.
(T/P91, T/P92, T911, T/P122)Weld Seam 180~270 
WB36ASME code case2353,≤252180~252The weld seam must not be less hard than the base material.
A515, A106B, A106C, A672 B70 type pipe fittings 130~197The lower limit of the weld seam must not be less than the base material, with the upper limit≤241.
12CrMoGB3077,≤179120~179 
15CrMoJB4726,118~180(Rm:440~610)JB4726,115~178(Rm:430~600)118~180115~178 
12Cr1MoVGB3077,≤179135~179 
15Cr1Mo1V 135~180 
F2(Forged or Rolled Pipe Fittings, Valves, and Components)ASTM A182,143~192143~192 
F11,Class 1ASTM A182,121~174121~174 
F11,Class 2ASTM A182,143~207143~207 
F11,Class 3ASTM A182,156~207156~207 
F12,Class 1ASTM A182,121~174121~174 
F12,Class 2ASTM A182,143~207143~207 
F22,Class 1ASTM A182, ≤170130~170 
F22,Class 3ASTM A182,156~207156~207 
F91ASTM A182, ≤248175~248 
F92ASTM A182, ≤269180~269 
F911ASTM A182, 187~248187~248 
F122ASTM A182, ≤250177~250 
20 Pressure Vessel Carbon Steel and Low Alloy Steel ForgingsJB4726,106~159106~159 
35 (Note: The Rm in the table refers to the tensile strength of the material, measured in MPa.)JB4726,136~200(Rm:510~670)JB4726,130~190(Rm:490~640)136~200130~190 
16MnJB4726,121~178(Rm:450~600)121~178 
20MnMoJB4726,156~208(Rm:530~700)JB4726,136~201(Rm:510~680)JB4726,130~196(Rm:490~660)156~208136~201130~196 
35CrMoJB4726,185~235(Rm:620~790)JB4726,180~223(Rm:610~780)185~235180~223 
0Cr18Ni90Cr17Ni12Mo2JB4728,139~187(Rm:520)JB4728,131~187(Rm:490)139~187131~187Stainless Steel Forgings for Pressure Vessels
1Cr18Ni9GB1220 ≤187140~187 
0Cr17Ni12Mo2GB1220 ≤187140~187 
0Cr18Ni11NbGB1220 ≤187140~187 
TP304H, TP316H, TP347HASTM A213,≤192140~192 
1Cr13 192~211Moving Blades
2Cr13 212~277Moving Blades
1Cr11MoV 212~277Moving Blades
1Cr12MoWV 229~311Moving Blades
ZG20CrMoJB/T 7024,135~180135~180 
ZG15Cr1MoJB/T 7024,140~220140~220 
ZG15Cr2Mo1JB/T 7024,140~220140~220 
ZG20CrMoVJB/T 7024,140~220140~220 
ZG15Cr1Mo1VJB/T 7024,140~220140~220 
35DL/T439,146~196146~196Bolt
45DL/T439,187~229187~229Bolt
20CrMoDL/T439,197~241197~241Bolt
35CrMoDL/T439,241~285241~285Bolt(Dia.>50mm)
35CrMoDL/T439,255~311255~311Bolt(Dia.≤50mm)
42CrMoDL/T439,248~311248~311Bolt(Dia.>65mm)
42CrMoDL/T439,255~321255~321Bolt(Dia.≤65mm)
25Cr2MoVDL/T439,248~293248~293Bolt
25Cr2Mo1VDL/T439,248~293248~293Bolt
20Cr1Mo1V1DL/T439,248~293248~293Bolt
20Cr1Mo1VTiBDL/T439,255~293255~293Bolt
20Cr1Mo1VNbTiBDL/T439,252~302252~302Bolt
20Cr12NiMoWV(C422)DL/T439,277~331277~331Bolt
2Cr12NiW1Mo1VEastern Steam Turbine Factory Standard291~321Bolt
2Cr11Mo1NiWVNbNEastern Steam Turbine Factory Standard290~321Bolt
45Cr1MoVEastern Steam Turbine Factory Standard248~293Bolt
R-26(Ni-Cr-Co Alloy)DL/T439,262~331262~331Bolt
GH445DL/T439,262~331262~331Bolt
ZG20CrMoJB/T7024,135~180135~180Cylinder
ZG15Cr1Mo, ZG15Cr2MoZG20Cr1MoV, ZG15Cr1Mo1VJB/T7024,140~220140~220Cylinder

Non-ferrous Metal Hardness Table

Non-ferrous Metal HardnessTensile strength
δb/MPa
RockwellSurface RockwellVickersBrinell
(F/D2=30) 
HRCHRAHR15NHR30NHR45NHVHBSHBWMSCr.SCr-V.SCrNi.SCr-Mo.SCr-Ni-Mo .SCrMnSi.SUHSSS.S
20.060.268.840.719.2226225225774742736782747/781/740
20.560.469.041.219.8228227227784751744787753/788/749
21.060.769.341.720.4230229229793760753792760/794/758
21.561.069.542.221.0233232232803769761797767/801/767
22.061.269.842.621.5235234234813779770803774/809/777
22.561.570.043.122.1238237237823788779809781/816/786
23.061.770.343.622.724l240240833798788815789/824/796
23.562.070.644.023.3244242242843808797822797/832/806
24.062.270.844.523.9247245245854818807829805/840/816
24.562.571.145.024.5250248248864828816836813/848/826
25.062.871.445.525.1253251251875838826843822/856/837
25.563.071.645.925.7256254254886848837851831850865/847
26.063.371.946.426.3259257257897859847859840859874/858
26.563.572.246.926.9262260260908870858867850869883/868
27.063.872.447.327.5266263263919880869876860879893/879
27.564.072.747.828.1269266266930891880885870890902/890
28.064.373.048.328.7273269269942902892894880901912/901
28.564.673.348.729.3276273273954914903904891912922/913
29.064.873.549.229.9280276276965925915914902923933/924
29.565.173.849.730.5284280280977937928924913935943/936
30.065.374.150.231.1288283283989948940935924947954/947
30.565.674.450.631.72922872871002960953946936959965/959
31.065.874.751.132.329629l29l1014972966957948972977/971
31.566.174.951.632.93002942941027984980969961985989/983
32.066.475.252.033.530429829810399969939819749991001/996
32.566.675.552.534.130830230210521009100799498710121013/1008
33.066.975.853.034.73133063061065102210221007100110271026/1021
33.567.176.153.435.33173103101078103410361020101510411039/1034
34.067.476.453.935.932l3143141092104810511034102910561052/1047
34.567.776.754.436.53263183181105106110671048104310711066/1060
35.067.977.054.837.033l3233231119107410821063105810871079/1074
35.568.277.255.337.63353273271133108810981078107411031094/1087
36.068.477.555.838.23403323321147110211141093109011191108/1101
36.568.777.856.238.83453363361162111611311109110611361123/1116
37.069.078.156.739.43503413411177113111481125112211531139/1130
37.569.278.457.240.03553453451192114611651142113911711155/1145
38.069.578.757.640.63603503501207116111831159115711891171/1161
38.569.779.058.141.2365355355122211761201117711741207118711701176
39.070.079.358.641.837l360360123811921219119511921226120411951193
39.570.379.659.042.4376365365125412081238121412111245122212191209
40.070.579.959.543.0381370370127112251257123312301265124012431226
40.570.880.260.043.6387375375128812421276125212491285125812671244
41.071.180.560.444.2393380381130512601296127312691306127712901262
41.571.380.860.944.8398385386132212781317129312891327129613131280
42.071.681.161.345.440439l392134012961337131413101348131613361299
42.571.881.461.845.9410396397135913151358133613311370133613591319
43.072.181.762.346.541640l403137813351380135813531392135713811339
43.572.482.062.747.1422407409139713551401138013751415137814041361
44.072.682.363.247.7428413415141713761424140413971439140014271383
44.572.982.663.648.3435418422143813981446142714201462142214501405
45.073.282.964.148.944l424428145914201469145114441487144514731429
45.573.483.264.649.5448430435148114441493147614681512146914961453
46.073.783.565.050.145443644l150314681517150214921537149315201479
46.573.983.765.550.746l442448152614931541152715171563151715441505
47.074.284.065.951.2468449455155015191566155415421589154315691533
47.574.584.366.451.8475/463157515461591158115681616156915941562
48.074.784.666.852.4482/470160015741617160815951643159516201592
48.575.084.967.353.0489/478162616031643163616221671162316461623
49.075.385.267.753.6497/486165316331670166516491699165116741655
49.575.585.568.254.2504/494168116651697169516771728167917021689
50.075.885.768.654.7512502502171016981724172417061758170917311725
50.576.186.069.155.3520510510/1732175217551735178817391761/
51.076.386.369.555.9527518518/1768178017861764181917701792/
51.576.686.670.056.5535527527/1806180918181794185018011824/
52.076.986.870.457.1544535535/1845183918501825188118341857/
52.577.187.170.957.6552544544//186918831856191418671892/
53.077.487.471.358.2561552552//189919171888194719011929/
53.577.787.671.858.856956l56l//19301951//19361966/
54.077.987.972.259.4578569569//19611986//19712006/
54.578.288.172.659.9587577577//19932022//20082047/
55.078.588.473.160.5596585585//20262058//20452090/
55.578.788.673.561.1606593593///////2135/
56.079.088.973.961.7615601601///////2181/
56.579.389.174.462.2625608608///////2230/
57.079.589.474.862.8635616616///////2281/
57.579.889,675.263.4645622622///////2334/
58.080.189.875.663.9655628628///////2390/
58.580.390.076.164.5666634634///////2448/
59.080.690.276.565.1676639639///////2509/
59.580.990.476.965.6687643643///////2572/
60.081.290.677.366.2698647647/////////
60.581.490.877.766.8710650650/////////
61.081.791.078.167.372l///////////
61.582.091.278.667.9733///////////
62.082.291.479.068.4745///////////
62.582.591.579.469.0757///////////
63.082.891.779.869.5770///////////
63.583.191.880.270.1782///////////
64.083.391.980.670.6795///////////
64.583.692.181.071.2809///////////
65.083.992.281.371.1822///////////
65.584.1///836///////////
66.084.4///850///////////
66.584.7///865///////////
67.085.0///879///////////
67.585.2///894///////////
68.085.5///909///////////

Ferrous Metal Hardness Table

The following data is mainly applicable to low-carbon steel (mild steel).

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Ferrous Metal HardnessTensile strength
RockwellSurface RockwellVickersBrinell HBS
HRBHR15THR30THR45THVF/D2=10F/D2=10MPa
60.080.456.130.4105102/375
60.580.556.430.9105102/377
61.080.756.731.4106103/379
61.580.857.131.9107103/381
62.080.957.432.4108104/382
62.581.157.732.9108104/384
63.081.258.033.5109105/386
63.581.458.334.0110105/388
64.081.558.734.5110106/390
64.581.659.035.011l106/393
65.081.859.335.5112107/395
65.581.959.636.1113107/397
66.082.159.936.6114108/399
66.582.260.337.1115108/402
67.082.360.637.6115109/404
67.582.560.938.1116110/407
68.082.661.238.6117110/409
68.582.761.539.2118111/412
69.082.961.939.7119112/415
69.583.062.240.2120112/418
70.083.262.540.712l113/42l
70.583.362.841.2122114/424
71.083.463.141.7123115/427
71.583.663.542.3124115/430
72.083.763.842.8125116/433
72.583.964.143.3126117/437
73.084.064.443.8128118/440
73.584.164.744.3129119/444
74.084.365.144.8130120/447
74.584.465.445.413l12l/451
75.084.565.745.9132122152455
75.584.766.046.4134123155459
76.084.866.346.9135124156463
76.585.066.647.4136125158467
77.085.167.047.9138126159471
77.585.267.348.513912716l475
78.085.467.649.0140128163480
78.585.567.949.5142129164484
79.085.768.250.0143130166489
79.585.868.650.5145132168493
80.085.968.951.0146133170498
80.586.169.251.6148134172503
81.086.269.552.1149136174508
81.586.369.852.6151137/513
82.086.570.253.1152138/518
82.586.670.553.6154140/523
83.086.870.854.1156//529
83.586.971.154.7157//534
84.087.071.455.2159//540
84.587.271.855.716l//546
85.087.372.156.2163//551
85.587.572.456.7165//557
86.087.672.757.2166//563
86.587.773.057.8168//570
87.087.973.458.3170//576
87.588.073.758.8172//582
88.088.174.059.3174//589
88.588.374.359.8176//596
89.088.474.660.3178//603
89.588.675.060.9180//609
90.088.775.361.4183/176617
90.588.875.661.9185/178624
91.089.075.962.4187/18063l
91.589.176.262.9189/182639
92.089.376.663.4191/184646
92.589.476.964.0194/187654
93.089.577.264.5196/189662
93.589.777.565.0199/192670
94.089.877.865.5201/195678
94.589.978.266.0203/197686
95.590.178.566.5206/200695
95.090.278.867.1208/203703
96.090.479.167.6211/206712
96.590.579.468.1214/209721
97.090.679.868.6216/212730
97.590.880.169.1219/215739
98.090.980.469.6222/218749
98.591.180.770.2225/222758
99.091.281.070.7227/226768
99.591.381.471.2230/229778
100.091.581.771.7233/232788

Common HV = HB = HRC Hardness Comparison Table

Hardness testing is the simplest and most straightforward method among mechanical property tests. In order to replace certain mechanical property tests with hardness tests, a relatively accurate conversion relationship between hardness and strength is needed in production.

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Experience has shown that there is an approximate corresponding relationship between the various hardness values of metal materials, and between hardness values and strength values. This is because the hardness value is determined by the initial plastic deformation resistance and the continued plastic deformation resistance. The higher the strength of the material, the higher the plastic deformation resistance, and thus the higher the hardness value.

Below is a quick calculator created by our site, based on empirical formulas obtained from experiments. It has practical value, but when accurate data is required, testing is still necessary.

Tensile strength
N/mm2
Vickers hardnessBrinell hardnessRockwell hardness
RmHVHBHRC
2508076
2708580.7
2859085.2
3059590.2
32010095
33510599.8
350110105
370115109
380120114
400125119
415130124
430135128
450140133
465145138
480150143
490155147
510160152
530165156
545170162
560175166
575180171
595185176
610190181
625195185
640200190
660205195
675210199
690215204
705220209
720225214
740230219
755235223
77024022820.3
78524523321.3
80025023822.2
82025524223.1
83526024724
85026525224.8
86527025725.6
88027526126.4
90028026627.1
91528527127.8
93029027628.5
95029528029.2
96530028529.8
99531029531
103032030432.2
106033031433.3
109534032334.4
112535033335.5
111536034236.6
119037035237.7
122038036138.8
125539037139.8
129040038040.8
132041039041.8
135042039942.7
138543040943.6
142044041844.5
145545042845.3
148546043746.1
152047044746.9
155748045647
159549046648.4
163050047549.1
166551048549.8
170052049450.5
174053050451.1
177554051351.7
181055052352.3
184556053253
188057054253.6
192058055154.1
195559056154.7
199560057055.2
203061058055.7
207062058956.3
210563059956.8
214564060857.3
218065061857.8
66058.3
67058.8
68059.2
69059.7
70060.1
72061
74061.8
76062.5
78063.3
80064
82064.7
84065.3
86065.9
88066.4
90067
92067.5
940

Hardness comparison table of common ferrous metals (Approximate conversion of intensity)

RockwellRockwellVickersBrinellTensile strength
HRCHRAHVHBN/mm2
17211211710
17.5214214715
18216216725
18.5218218730
19221220735
19.5223222745
20226225750
20.5229227760
21231229765
21.5234232775
22237234785
22.5240237790
23243240800
23.5246242810
24249245820
24.5252248830
25255251835
25.5258254850
26261257860
26.5264260870
27268263880
27.5271266890
28274269900
28.5278273910
29281276920
29.5285280935
30289283950
30.5292287960
31296291970
31.5300294980
32304298995
32.53083021010
333123061020
33.53163101035
343203141050
34.53243181065
353293231080
35.53333271095
363383321110
36.53423361125
373473411140
37.53523451160
383573501175
38.53623551190
39703673601210
39.570.33723651225
4070.83823751260
40.570.53773701245
4171.13883801280
41.571.33933851300
4271.63993911320
42.571.84053961340
4372.14114011360
43.572.44174071385
4472.64234131405
44.572.94294181430
4573.24364241450
45.573.44434301475
4673.74494361500
46.573.94564421525
4774.24634491550
47.574.54704551575
4874.74784611605
48.5754854681630
4975.34934741660
49.575.55014811690
5075.85094881720
50.576.15174941750
5176.35255011780
51.576.65341815
5276.95431850
52.577.15511885
5377.45611920
53.577.75701955
5477.95791995
54.578.25892035
5578.55992075
55.578.76092115
56796202160
56.579.36312205
5779.56422250
57.579.86532295
5880.16642345
58.580.36762395
5980.66882450
59.580.97002500
6081.27132555
60.581.4726
6181.7739
61.582752
6282.2766
62.582.5780
6382.8795
63.583.1810
6483.3825
64.583.6840
6583.9856
65.584.1872
6684.4889
66.584.7906
6785923
67.585.2941
6885.5959
68.585.8978
6986.1997
69.586.31017
7086.61037

Download Ferrous & Non-ferrous Metal Hardness Table

Metal hardness and strength conversion value, strength and hardness comparison table

HRC / HB Approximate Conversion Tips

  • When the hardness is higher than 20HRC, 1HRC≈10HB,
  • When the hardness is lower than 20HRC, 1HRC≈11.5HB.

Note: When considering cutting processing, a general conversion of 1HRC ≈ 10HB applies (the hardness of the workpiece material may vary slightly).

The most commonly used indentation hardness tests for metal materials are Brinell, Rockwell, and Vickers hardness tests.

The hardness value indicates a material’s ability to resist plastic deformation caused by the intrusion of another object.

When measuring hardness using the rebound method, the hardness value represents the extent of the metal’s elastic deformation function.

Commonly Used Hardness

Brinell Hardness

The Brinell hardness test uses a ball made of hardened steel or a hard alloy with a diameter of D as the indenter.

A specified test force F is applied to the surface of the material being tested, and after a designated hold time, the test force is removed, leaving an indentation with a diameter of d.

The Brinell hardness value is calculated by dividing the test force by the surface area of the indentation. The symbol for the Brinell hardness value is represented as HBS or HBW.

Brinell Hardness

The difference between HBS and HBW lies in the type of indenter used.

HBS indicates the use of a hardened steel ball as the indenter and is used to determine the Brinell hardness of materials with a value less than 450, such as mild steel, gray cast iron, and non-ferrous metals.

HBW, on the other hand, refers to the use of a hard alloy ball as the indenter and is used to measure the Brinell hardness of materials with a value below 650.

Even when the same material and experimental conditions are used, the results of the two tests may vary, with the HBW value typically being higher than the HBS value, and there is no exact quantitative rule to follow.

HBW Formula

In 2003, China adopted international standards and discontinued the use of steel ball indenters in favor of hard alloy ball heads.

As a result, HBS was no longer used and all Brinell hardness values are now represented by HBW.

Although HBW is often simply referred to as HB, references to HBS may still be found in literature.

The Brinell hardness measurement method is suitable for testing materials such as cast iron, non-ferrous alloys, and various steels that have undergone annealing or quenching and tempering processes.

However, it is not suitable for testing samples or workpieces that are too hard, too small, too thin, or do not allow for large indentations on the surface.

Rockwell Hardness

The Vickers hardness test uses either a diamond cone with a 120-degree cone apex angle or a hardened steel ball with a diameter of Ø1.588mm or Ø3.176mm as the indenter, along with a specified load.

The sample is subjected to an initial load of 10kgf and a total load of 60, 100, or 150kgf.

After the total load is applied, the hardness is determined by the difference in indentation depth when the main load is removed while retaining the initial load and the indentation depth under the initial load.

Rockwell Hardness

The Rockwell hardness test uses three different test forces and three different indenters, resulting in a total of nine possible combinations and corresponding Rockwell hardness scales.

These nine scales are suitable for a wide range of commonly used metal materials.

The three most commonly used Rockwell hardness scales are HRA, HRB, and HRC, with HRC being the most widely utilized.

Table of commonly used Rockwell hardness test specifications

Hardness symbolIndenter typeTotal test force
F/N(kgf)
Hardness rangeApplications
HRA120°diamond cone588.4(60)20~88Hard alloy, carbide, shallow case hardening steel and etc.
HRBØ1.588mm Quenched steel ball980.7(100)20~100Annealed or normalized steel, aluminum alloy, copper alloy, cast iron
HRC120°diamond cone1471(150)20~70Hardened steel, quenched and tempered steel, deep case hardening steel

The Rockwell hardness test is appropriate for hardness values ranging from 20-70HRC. If the hardness of the sample is less than 20HRC, it is recommended to use the HRB scale as the sensitivity of the indenter decreases with increased pressure on the conical part.

However, if the hardness of the sample is greater than 67HRC, it is advised to use the HRA scale as the pressure on the tip of the indenter may become too high and result in damage to the diamond and reduced life of the indenter.

The Rockwell hardness test is known for its ease, speed, and minimal indentation, making it ideal for testing the surface of finished products and harder, thinner workpieces.

However, due to the small indentation, the hardness value may fluctuate greatly for materials with uneven structures and hardness, making it less accurate than the Brinell hardness test.

The Rockwell hardness test is commonly used to determine the hardness of materials such as steel, non-ferrous metals, and cemented carbides.

Vickers Hardness

Vickers Hardness

The principle behind the Vickers hardness measurement is similar to that of the Brinell hardness test.

A diamond pyramid-shaped indenter with an angle of 136° is used to apply a specified test force, F, onto the surface of the material being tested.

After a specified holding time, the test force is removed, and the hardness value is calculated as the average pressure on the unit surface area of the regular pyramid-shaped indentation, with the symbol HV.

HV Formula

The Vickers hardness measurement has a wide range, and it can measure materials with a hardness ranging from 10 to 1000 HV. The indentation is small in size.

This measurement method is commonly used to measure thin materials and surface-hardened layers created through carburizing and nitriding.

Leeb Hardness

The Leeb Hardness Test uses a device equipped with a tungsten carbide ball to impact the surface of the test piece, which then rebounds. The speed of the rebound is affected by the hardness of the material being tested.

A permanent magnetic material is installed on the impact device, which produces an electromagnetic signal proportional to the speed of the impact body’s movement. This signal is then converted into a Leeb hardness value by an electronic circuit, represented by the symbol HL.

The Leeb Hardness Tester is a handheld device that does not require a workbench. Its hardness sensor is compact and can be easily operated by hand, making it suitable for testing large, heavy, or complex geometries.

One of the key benefits of the Leeb Hardness Test is that it results in only light surface damage, making it an ideal option for non-destructive testing. It also provides a unique hardness test for all directions, narrow spaces, and special parts.

Hardness Testers

  • Micro Vickers hardness testing machine

HM series:

Micro Vickers hardness testing machine

  • Vickers hardness testing machine
    HV series:
Vickers hardness testing machine

  • Rockwell hardness testing machine
    HR series:
Rockwell hardness testing machine

  • Portable Leeb hardness tester
    HH series:
Portable Leeb hardness tester

FAQs About Metal Hardness

How to measure hardness of metal?

The most commonly used methods to measure the hardness of metal are the Brinell hardness method, the Rockwell hardness method, and the Vickers hardness method.

How to increase metal hardness?

The strength of metal materials can be improved through the following five methods:

1) Conducting a heat treatment process, such as quenching, tempering, normalizing, etc., based on the required performance and structure.

2) Surface shot peening.

3) Grain boundary strengthening.

4) Dislocation strengthening.

5) Precipitation of certain compounds through deformation and aging, which can improve strength.

At what temperature does metal lose hardness?

At temperatures below -200 degrees Celsius, ordinary steel becomes as brittle as glass.

The low temperature reduces the cohesive forces between metal molecules, making the material more rigid and less able to withstand deformation. This increased rigidity causes the metal to become more prone to breaking under external force.

However, it is important to note that the brittleness of the metal is dependent on the specific situation.

For example, materials with a face-centered cubic structure do not undergo a transition from ductile to brittle behavior at low temperatures.

What determines the hardness of a metal?

1)The hardness of a metal is determined by the strength of the bonding between metal atoms.

2)The harder the metal, the stronger the bonding between the metal atoms and the smaller the radius of the metal atoms.

3)The more valence electrons in the metal atoms per unit volume, the stronger the bonding between the metal atoms and the greater the hardness.

4)In general, for main group metals, moving from left to right within the same period, the atomic radius decreases and the number of valence electrons increases, leading to an increase in hardness.

On the other hand, moving from top to bottom within the same main group, the atomic radius increases while the number of valence electrons remains constant, resulting in a decrease in hardness.

5)For transition elements, the atomic radius decreases from left to right, but the number of valence electrons increases first and then decreases, making the trend in hardness less clear-cut than for the main family elements.

However, elements with high hardness are typically found in the middle of the transition elements within the same period.

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