Is it possible to change the hardness of material?
How can we check the hardness of the material?
How hardness and toughness of a material are measured?
What is HRB in hardness?

Hardness conversion chart for stainless steel 304L 321 309S stainless plate.

Hardness conversion chart

The approximate conversion values of Vickers Hardness (HV) of steel with other hardness and strength

There are many kinds of hardness test methods, such as rockwell hardness, brinell and vickers hardness, knoop hardness, hardness, Webster’s hardness and barcol hardness on the Richter scale, each kind of test method includes different test conditions, such as the size of the test force and loading method, the type of pressure head and materials, this creates in different countries, industries and units used in hardness is not uniform. In order to convert from one hardness unit to another, a hardness conversion table or hardness conversion tool is needed.

According to GB/T 1172-1999 “Conversion Values for Hardness and Strength of ferrous Metals”, a more accurate conversion value for hardness can be obtained only when the specimens are uniformly organized. Therefore, the use of hardness conversion tables should be avoided as far as possible, and the appropriate traditional hardness tester should be used directly for testing.

Common hardness conversion tables include:

GB/T 1172-1999

ASTM E140

ISO 18265

Vickers hardness Brinell hardness

10 – mm steel ball

The 3000 – kg load b

 Rockwell hardness b Surface Rockwell hardness

Surface diamond taper indenter

 Shore hardness Tensile strength (approximate)Mpa

(1000psi)

 Vickers hardness
Standard steel ball Tungsten – hard alloy steel ball Ruler 60-kg load diamond cone indenter Ruler

100-kgLoad diamond cone indenter

 Ruler

100-kgLoad diamond cone indenter

 Ruler

100-kgLoad diamond cone indenter

 15-N

Ruler

15－kg

Load

 30-N ruler 30-kg load 45-N ruler 45-kg load
HV HBS HBW HRA HRB HRC HRD HR15N HR30N HR45N HS σb HV
1 2 3 4 5 6 7 8 9 10 11 12 13
370 350 350 69.2 － 37.7 53.6 79.2 57.4 40.4 － 1170(170) 370
360 341 341 68.7 -109 36.6 52.8 78.6 56.4 39.1 50 1130(164) 360
350 331 331 68.1 － 35.5 51.9 78 55.4 37.8 － 1095(159) 350
340 322 322 67.6 -108 34.4 51.1 77.4 54.4 36.5 47 1070(155) 340
330 313 313 67 － 33.3 50.2 76.8 53.6 35.2 － 1035(150) 330
320 303 303 66.4 -107 32.3 49.4 76.2 52.3 33.9 45 1005(146) 320
310 294 294 65.8 － 31 48.4 75.6 51.3 32.5 － 980(142) 310
300 284 284 65.2 -105.5 29.8 47.5 74.9 50.2 31.1 42 950(138) 300
295 280 280 65.8 － 29.2 47.1 74.6 49.7 30.4 － 935(136) 295
290 275 275 64.5 -104.5 28.5 46.5 74.2 49 29.5 41 915(133) 290
285 270 270 64.2 － 27.8 46 73.8 48.4 28.7 － 905(131) 285
280 265 265 63.8 -103.5 27.1 45.3 73.4 47.8 27.9 40 890(129) 280
275 261 261 63.5 － 26.4 44.9 73 47.2 27.1 － 875(127) 275
270 256 256 63.1 -102 25.6 44.3 72.6 46.4 26.2 38 855(124) 270
265 252 252 62.7 － 24.8 43.7 72.1 45.7 25.2 － 840(122) 265
260 247 247 62.4 -101 24 43.1 71.6 45 24.3 37 825(120) 260
255 243 243 62 － 23.1 42.2 71.1 44.2 23.2 -36 805(117) 255
250 238 238 61.6 99.5 22.2 41.7 70.6 43.4 22.2 － 795(115) 250
245 233 233 61.2 － 21.3 41.1 70.1 42.5 21.1 34 780(113) 245
240 228 228 60.7 98.1 20.3 40.3 69.6 41.7 19.9 33 765(111) 240
230 219 219 － 96.7 -18 － － － － 32 730(106) 230
220 209 209 － 95 -15.7 － － － － 30 695(101) 220
210 200 200 － 93.4 -13.4 － － － － 29 670(97) 210
200 190 190 － 91.5 -11 － － － － 28 635(92) 200
190 181 181 － 89.5 -8.5 － － － － 26 605(88) 190
180 171 171 － 87.1 -6 － － － － 25 580(84) 180
170 162 162 － 85 -3 － － － － 24 545(79) 170
160 152 152 － 81.7 0 － － － － 22 515(75) 160
150 143 143 － 78.7 － － － － － 21 490(71) 150
140 133 133 ― 75 － － － － － 20 455(66) 140
130 124 124 ― 71.2 － － － － － － 425(62) 130
120 114 114 － 66.7 － － － － － － 390(57) 120
110 105 105 － 62.3 － － － － － － － 110
100 95 95 － 56.2 － － － － － － － 100
95 90 90 － 52 － － － － － － － 95
90 86 86 － 48 － － － － － － － 90
85 81 81 － 41 － － － － － －

A) The values indicated in bold in this table are consistent with the hardness conversion values in Table 1 of ASTM-E140, as listed by the corresponding SAE-ASM-ASTM Federation. B) The values in parentheses are out of range and are for reference only.

Is it possible to change the hardness of material?
How can we check the hardness of the material?
How hardness and toughness of a material are measured?
What is HRB in hardness?

More date in following

Rockwell Hardness Surface Rockwell hardness Vickershardness Brinell hardness Shore Hardness
HRA HRB HRC HRD 15N 30N 45N HV HB HS
60kgf 100kgf 150kgf 100kgf 15kgf 30kgf 45kgf 50kgf 3000kgf JIS
85.6   68 76.9 93.2 84.4 75.4 940   97.6
85.3   67.5 76.5 93 84 74.3 920   96.4
85   67 76.1 92.9 83.6 74.2 900   95.2
84.7   66.5 75.7 92.7 83.1 73.6 880   94
84.4   65.9 75.3 92.5 82.7 73.1 860   92.8
84.1   65.3 74.8 92.3 82.2 72.2 840   91.5
83.8   64.7 74.3 92.1 81.7 71.8 820   90.2
83.4   64 73.8 91.8 81.1 71 800   88.9
83   63.3 73.3 91.5 80.4 70.2 780   87.5
82.6   62.5 72.6 91.2 79.7 69.4 760   86.2
82.2   61.8 72.1 91 79.1 68.6 740   84.8
81.8   61 71.5 90.7 78.4 67.7 720   83.3
81.3   60.1 70.8 90.3 77.6 66.7 700   81.8
81.1   59.7 70.5 90.1 77.2 66.2 690   81.1
80.8   59.2 70.1 89.8 76.8 65.7 680   80.3
80.6   58.8 69.8 89.7 76.4 65.3 670   79.6
80.3   58.3 69.4 89.5 75.9 64.7 660   78.8
80   57.8 69 89.2 75.5 64.1 650   78
79.8   57.3 68.7 89 75.1 63.5 640   77.2
79.5   56.8 68.3 88.8 74.6 63 630   76.4
79.2   56.3 67.9 88.5 74.2 62.4 620   75.6
78.9   55.7 67.5 88.2 73.6 61.7 610   74.7
78.6   55.2 67 88 73.2 61.2 600   73.9
78.4   54.7 66.7 87.8 72.7 60.5 590   73.1
78   54.1 66.2 87.5 72.1 59.9 580   72.2
77.8   53.6 65.8 87.2 71.7 59.3 570   71.3
77.4   53 65.4 86.9 71.2 58.6 560   70.4
77   52.3 64.8 86.6 70.5 57.8 550 505 69.6
76.7   51.7 64.4 86.3 70 57 540 496 68.7
76.4   51.1 63.9 86 69.5 56.2 530 488 67.7
76.1   50.5 63.5 85.7 69 55.6 520 480 66.8
75.7   49.8 62.9 85.4 68.3 54.7 510 473 65.9
75.3   49.1 62.2 85 67.7 53.9 500 465 64.9
74.9   48.4 61.6 84.7 67.1 53.1 490 456 64
74.5   47.7 61.3 84.3 66.4 52.2 480 448 63
74.1   46.9 60.7 83.9 65.7 51.3 470 441 62
73.6   46.1 60.1 83.6 64.9 50.4 460 433 61
73.3   45.3 59.4 83.2 64.3 49.4 450 425 60
72.8   44.5 58.8 82.8 63.5 48.4 440 415 59
72.3   43.6 58.2 82.3 62.7 47.4 430 405 58
71.8   42.7 57.5 81.8 61.9 46.4 420 397 56.9
71.4   41.8 56.8 81.4 61.1 45.3 410 388 55.9
70.8   40.8 65 81 60.2 44.1 400 379 54.8
70.3   39.8 55.2 80.3 59.3 42.9 390 369 53.7
69.8 110 38.8 54.4 79.8 58.4 41.7 380 360 52.6
69.2   37.7 53.6 79.2 57.4 40.4 370 350 51.5
68.7 109 36.6 52.8 78.6 56.4 39.1 360 341 50.4
68.1   35.5 51.9 78 55.4 37.8 350 331 49.3
67.6 108 34.4 51.1 77.4 54.4 36.5 340 322 48.1
67   33.3 50.2 76.8 53.6 35.2 330 313 47
66.4 107 32.2 49.4 76.2 52.3 33.9 320 303 45.8
65.8   31.6 48.4 75.8 51.8 32.8 310 294 44.6
65.2 105.5 29.8 47.5 74.9 50.2 31.1 300 284 43.4
64.8   29.2 47.1 74.6 49.7 30.4 295 280 42.8
64.5 104.5 28.5 46.5 74.2 49 29.5 290 275 42.2
64.2   27.8 46 73.8 48.4 28.7 285 270 41.6
63.8 103.5 27.1 45.3 73.4 47.8 27.9 280 265 40.9
63.5   26.4 44.9 73 47.2 27.1 275 261 40.3
63.1 102 25.6 44.3 72.6 46.4 26.2 270 256 39.7
62.7   24.8 43.7 72.1 45.7 25.2 265 252 39
62.4 101 24 43.1 71.6 45 24.3 260 247 38.4
62   23.1 42.2 71.1 44.2 23.2 255 243 37.8
61.6 99.5 22.2 41.7 70.6 43.4 22.2 250 238 37.2
61.2   21.3 41.1 70.1 42.5 21.1 245 233 36.5
60.7 98.1 20.3 40.3 69.6 41.7 19.9 240 228 35.9
  96.7 18         230 219 34.1
  95 15.7         220 209 33.2
  93.4 13.4         210 200 31.8
  91.5 11         200 190 30.4
  89.5 8.5         190 181 29
  87.1 6         180 171 27.7
  85 3         170 162 26.5
  81.7 0         160 152 25
  78.7           150 143 23.7
  78           140 133 22.1
  71.2           130 124 20.6
  66.7           120 114 19.1
  62.3           110 105 17.6
  56.2           100 95 16.1

Note: The above table includes Rockwell hardness and surface Rockwell hardness. What is the difference? To put it simply, if the parts are relatively thin, such as the following tube-walled parts:

Because the wall of such a product is thin, the ordinary Rockwell hardness test indenter directly flattens the product, but this does not mean that the part itself has no hardness, so in this case, the surface Rockwell hardness measurement method is used.

 

The surface Rockwell hardness measurement method is based on the ordinary Rockwell hardness measurement and lowers the detection force (of course, there are some other small differences such as the angle of the indenter, etc., which I will not go into). It is specially suitable for parts with thin walls or parts that have undergone surface heat treatment (such as carburization).

 

The differences between Rockwell, Vickers, Brinell, and Shore measurement methods are all based on different measurement methods and matching objects. This page will not go into details.

 

Hardness conversion table for soft metals (such as copper and aluminum)

Rockwell hardness Surface Rockwell hardness Vickers Hardness
HRB HRF 15T 30T 45T HV
100kgf 60kgf 15kgf 30kgf 45kgf 50kgf
93.5 110 90 77.5 66 196
  109.5     65.5 194
93     77 65 192
92.5 109   76.5 64.5 190
92   89.5   64 188
91.5 108.5   76 63.5 186
91     75.5 63 184
90.5 108 89   62.5 182
90 107.5   75 62 180
89     74.5 61.5 178
88.5 107     61 176
88   88.5 74 60.5 174
87.5 106.5   73.5 60 172
87       59.5 170
86 106 88 73 59 168
85.5     72.5 58.5 166
85 105.5   72 58 164
84 105 87.5   57.5 162
83.5     71.5 56.7 160
83 104.5   71 56 158
82 104 87 70.5 55.5 156
81.5 103.5   70 54.5 154
80.5 103     54 152
80   86.5 69.5 53.5 150
79 102.5   69 53 148
78 102   68.5 52.5 146
77.5 101.5 86 68 51.5 144
77 101   67.5 51 142
76 100.5 85.5 67 50 140
75 100   66.5 49 138
74.5 99.5 85 66 48 136
73.5 99   65.5 47.5 134
73 98.5 84.5 65 46.5 132
72 98 84 64.5 45.5 130
71 97.5   63.5 45 128
70 97 83.5 63 44 126
69 96.5   62.5 43 124
68 96 83 62 42 122
67 95.5   61 41 120
66 95 82.5 60.5 40 118
65 94.5 82 60 39 116
64 94 81.5 59.5 38 114
63 93 81 58.5 37 112
62 92.6 80.5 58 35.5 110
61 92   57 34.5 108
59.5 91.2 80 56 33 106
58 90.5 79.5 55 32 104
57 89.8 79 54.5 30.5 102
56 89 78.5 53.5 29.5 100
54 88 78 52.5 28 98
53 87.2 77.5 51.5 26.5 96
61.6 86.6 77 50.5 24.5 94
49.5 85.4 76.5 49 23 92
47.5 84.4 75.5 48 21 90
46 83.5 75 47 19 88
44 82.3 74.5 45.5 17 86
42 81.2 73.5 44 14.5 84
40 80 73 43 12.5 82
37.5 78.6 72 41 10 80
35 77.4 71.5 39.5 7.5 78
32.5 76 70.5 38 4.5 76
30 74.8 70 36 1 74
27.5 73.2 69 34   72
24.5 71.6 68 32   70
21.5 70 67 30   68
18.5 68.5 66 28   66
15.5 66.8 65 25.5   64
12.5 65 63.5 23   62
10 63 62.5 20.5   60
  61 61 18   58
  58.8 60 15   56
  56.5 58.5 12   54
  53.5 57     52
  50.5 55.5     50
  49 54.5     49
  47 53.5     48
  45       47
  43       46
  40       45