Patriot Forge — Brinell Hardness Tool

HB	HRC	HRB	HV	Tensile (MPa)
120	—	67	120	414
150	—	80	155	517
200	—	93	210	690
250	24	—	263	862
300	32	—	316	1034
350	38	—	370	1207
400	43	—	423	1379
450	47	—	481	1552
500	51	—	542	1724
600	57	—	668	2069

Steel Grade Hardness Ranges

1018 (Low Carbon)

Annealed: 126 HB · Carburized: 200–550 HB

1045 (Medium Carbon)

Annealed: 163 HB · Q&T: 200–370 HB

4130 (Chromoly)

Annealed: 156 HB · Q&T: 250–400 HB

4140 (Chromoly)

Annealed: 197 HB · Q&T: 280–420 HB

4340 (NiCrMo)

Annealed: 217 HB · Q&T: 280–500 HB

8620 (NiCrMo)

Annealed: 149 HB · Carburized: 200–550 HB

H13 (Tool Steel)

Annealed: 192 HB · Hardened: 444–555 HB

D2 (Tool Steel)

Annealed: 217 HB · Hardened: 555–614 HB

A36 (Structural)

As-rolled: 119–159 HB

304 Stainless

Annealed: 123–201 HB

316 Stainless

Annealed: 146–195 HB

410 Stainless

Annealed: 155 HB · Hardened: 350–420 HB

Brinell Test Quick Notes

Standard test (ASTM E10): 10mm ball, 3000 kgf, 10–15 sec dwell
Measure: Two diameters at 90° — use the average
Min thickness: ≥ 8× indentation depth
Spacing: Center of indent ≥ 2.5d from edge, ≥ 3d between centers
Surface: Clean, flat, smooth — grind if needed

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Brinell Hardness Calculator

Hardness Conversion

Common Conversions