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Bolt Nut Fastener

Hardness Conversion Table

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Use this table for comparing hardness of carbon steels, cast steels and low alloy steels in a heat treated and hot formed condition.

According to ISO 18265.

Tensile StrengthVickers Hardness HVBrinell Hardness*Rockwell hardness
N/mm2F ≥ 98 NHBHRBHRCHRA
2558076
2708580,741
2859085,548
3059590,252
3201009556,2
33510599,8
35011010562,3
370115109
38512011466,7
400125119
41513012471,2
430135128
45014013375
465145138
48015014378,7
495155147
51016015281,7
530165156
54517016285
560175166
57518017187,1
595185176
61019018189,5
625195185
64020019091,5
66020519592,5
67521019993,5
69021520494
70522020995
72022521496
74023021996,7
755235223
77024022898,120,360,7
78524523321,361,2
80025023899,522,261,6
820255242-10123,162
8352602472462,4
850265252-10224,862,7
86527025725,663,1
880275261-10426,463,5
90028026627,163,8
915285271-10527,864,2
93029027628,564,5
95029528029,264,8
96530028529,865,2
9953102953165,8
103032030432,266,4
106033031433,367
109534032334,367,6
112535033335,568,1
115536034236,668,7
119037035237,769,2
122038036138,869,8
125539037139,870,3
129040038040,870,8
132041039041,871,4
135042039942,771,8
138543040943,672,3
142044041844,572,8
145545042845,373,3
148546043746,173,6
152047044746,974,1
1555480-46547,774,5
1595490-46648,474,9
1630500-47549,175,3
1665510-48549,875,7
1700520-49450,576,1
1740530-50451,176,4
1775540-51351,776,7
1810550-52352,377
1845560-5325377,4
1880570-54253,677,8
1920580-55154,178
1955590-56154,778,4
1995600-57055,278,6
2030610-58055,778,9
2070620-58956,379,2
2105630-59956,879,5
2145640-60857,379,8
2180650-61857,880
66058,380,3
67058,880,6
68059,280,8
69059,781,1
70060,181,3
7206181,8
74061,882,2
76062,582,6
78063,383
8006483,4
82064,783,8
84065,384,1
86065,984,4
88066,484,7
9006785
92067,585,3
9406885,6
The figures in brackets represent hardness values beyond the defined scope of the standardised hardness test but which are frequently used as approximate values in practice. The Brinell hardness values in brackets are only valid if the test was carried out with a hard metal ball.

* Calculated with: HB = 0,95 · HV

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