Approximate Hardness Conversion Numbers for Steels

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Vickers
HV		 HB Rockwell Rockwell Super-ficial Shore
HS
Tensile
Strength
kg¡þmm2
Vickerw
HV
HRA HRB HRC HRD 15-N 30-N
45-N
940
920
900
880
860
-
-
-
-
-
85.6
85.3
85.0
84.7
84.4
-
-
-
-
-
68.0
67.5
67.0
66.4
65.9
76.9
76.5
76.1
75.7
75.3
93.2
93.0
92.9
92.7
92.5
84.4
84.0
83.6
83.1
82.7
75.4
74.8
74.2
73.6
73.1
97
96
95
93
92
-
-
-
-
-
940
920
900
880
860
840
820
800
780
760
-
-
-
-
-
84.1
83.8
83.4
83.0
82.6
-
-
-
-
-
65.3
64.7
64.0
63.3
62.5
74.8
74.3
73.8
73.3
72.6
92.3
93.1
91.8
91.5
91.2
82.2
81.7
81.1
80.4
79.7
72.2
71.8
71.0
70.2
69.4
91
90
88
87
86
-
-
-
-
-
840
820
800
780
760
740
720
700
690
680
-
-
-
-
-
82.2
81.8
81.3
81.1
80.8
-
-
-
-
-
61.8
61.0
60.1
59.7
59.2
72.1
71.5
70.8
70.5
70.1
91.0
90.7
90.3
90.1
89.3
79.1
78.4
77.6
77.2
76.8
68.6
67.7
66.7
66.2
65.7
84
83
81
-
80

-
-
-
-
-
740
720
700
690
680
670
660
650
640
630
-
-
-
-
-
80.6
80.3
80.0
79.8
79.5
-
-
-
-
-
58.8
58.3
57.8
57.3
56.8
69.8
69.4
69.0
68.7
68.3
89.7
89.5
89.2
89.0
88.8
76.4
75.9
75.5
75.1
74.6
65.3
64.7
64.1
63.5
63.0
-
79
-
77
-
-
-
-
-
-
670
660
650
640
630
620
610
600
590
580
-
-
-
-
-
79.2
78.9
78.6
78.4
78.0
-
-
-
-
-
56.3
55.7
55.2
54.7
54.1
67.9
67.5
67.0
66.7
66.2
88.5
88.2
88.0
87.8
87.5
74.2
73.6
73.2
72.7
72.1
62.4
61.7
61.2
60.5
59.9
75
-
74
-
72
-
-
-
210
206
620
610
600
590
580
570
560
550
540
530
-
-
(505)
(496)
(488)
77.8
77.4
77.0
76.7
76.4
-
-
-
-
-
53.6
53.0
52.3
51.7
51.1
65.8
65.4
64.8
64.4
63.9
87.2
86.9
86.6
86.3
86.0

71.7
71.2
70.5
70.0|
69.5
59.3
58.6
57.8
57.0
56.2
-
71
-
69
-
202
199
194
190
186
570
560
550
540
530
520
510
500
490
480
(480)
(473)
(465)
456
448
76.1
75.7
75.3
74.9
74.5
-
-
-
-
-
50.5
49.8
49.1
48.4
47.7
63.5
62.9
62.2
61.6
61.3
85.7
85.4
85.0
84.7
84.3
69.0
68.3
67.7
67.1
66.4
55.6
54.7
53.9
53.1
52.2
67
-
66
-
64
183
179
174
169
165
520
510
500
490
480
470
460
450
440
430
441
433
425
415
405
74.1
73.6
73.3
72.8
72.3
-
-
-
-
-
46.9
46.1
45.3
44.5
43.6
60.7
60.1
59.4
58.8
58.2
83.9
93.6
83.2
82.8
82.3
65.7
64.9
64.3
63.5
62.7
51.3
50.4
49.4
48.4
47.4
-
62
-
59
-
160
156
153
149
144
470
460
450
440
430
420
410
400
390
380
397
388
379
369
360
71.8
71.4
70.8
70.3
69.8
-
-
-
-
(110.0)
42.7
41.8
40.8
39.8
38.8
57.5
56.8
56.0
55.2
54.4
81.8
81.4
81.0
80.3
79.8
61.9
61.1
60.2
59.3
58.4
46.4
45.3
44.1
42.9
41.7
57
-
55
-
52
140
136
131
127
123
420
410
400
390
380
370
360
350
340
330
350
341
331
322
313
69.2
68.7
68.1
67.6
67.0
-
(109.0)
-
(108.0)
-
37.7
36.6
35.5
34.4
33.3
53.6
52.8
51.9
51.1
50.2
79.2
78.6
78.0
77.4
76.8
57.4
56.4
55.4
54.4
53.6
40.4
39.1
37.8
36.5
35.2
-
50
-
47
-
120
115
112
109
105
370
360
350
340
330
320
310
300
295
290
303
294
284
280
275
66.4
65.8
65.2
64.8
64.5
(107.0)
-
(105.5)
-
(104.5)
32.2
31.0
29.8
29.2
28.5
49.4
48.4
47.5
47.1
46.5
76.2
75.6
74.9
74.6
74.2
52.3
51.3
50.2
49.7
49.0
33.9
32.5
31.1
30.4
29.5
45
-
42
-
41
103
100
97
96
94
320
310
300
295
290
285
280
275
270
265
270
265
261
256
252
64.2
63.8
63.5
63.1
62.7
-
(103.5)
-
(102.0)
-
27.8
27.1
26.4
25.6
24.8
46.0
45.3
44.9
44.3
43.7
73.8
73.4
73.0
72.6
72.1
48.4
47.8
47.2
46.4
45.7
28.7
27.9
27.1
26.2
25.2
-
40
-
38
-
92
91
89
87
86
285
280
275
270
265
260
255
250
245
240
247
243
238
233
228
62.4
62.0
61.6
61.2
60.7
(101.0)
-
99.5
-
98.1
24.0
23.1
22.2
21.3
20.3
43.1
42.2
41.7
41.1
40.3
71.6
71.1
70.6
70.1
69.6
45.0
44.2
43.4
42.5
41.7
24.3
23.2
22.2
21.1
19.9
37
-
36
-
34
84
82
81
79
78
260
255
250
245
240
230
220
210
200
190
219
209
200
190
181
-
-
-
-
-
96.7
95.0
93.4
91.5
89.5
(18.0)
(15.7)
(13.4)
(11.0)
(8.5)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
33
32
30
29
28
75
71
68
65
62
230
220
210
200
190
180
170
160
150
140
171
162
152
143
133
-
-
-
-
-
87.1
85.0
81.7
78.7
75.0
(6.0)
(3.0)
(0.0)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
26
25
24
22
21
59
56
53
50
46
180
170
160
150
140