Hardness Comparison Table

BRINELL 3000 Kg. LOAD 10mm BALL		DIAMOND PYRAMID NUMBER (VICKERS) HV	ROCKWELL NUMBER		EQUIVALENT TENSILE STRENGTH FOR STEEL
Dia of Impression (mm)	Hardness Number HB	DIAMOND PYRAMID NUMBER (VICKERS) HV	C. Scale 150 kg Diamond Cone	B. Scale 100 kg 1/16 inch Ball	N/mm2	Tons/sq.in
2.05	899	–	–	–	3027	196
2.10	856	–	–	–	2888	187
2.15	817	–	–	–	2749	178
2.20	780	1150	70	–	2641	171
2.25	745	1050	68	–	2517	163
2.30	712	960	66	–	2409	156
2.35	682	885	64	–	2286	148
2.40	653	820	62	–	2193	142
2.45	627	765	60	–	2116	137
2.50	601	717	58	–	2023	131
2.55	578	675	57	–	1946	126
2.60	555	633	55	120	1869	121
2.65	534	598	53	119	1792	116
2.70	514	567	52	119	1730	112
2.75	495	540	50	117	1668	108
2.80	477	515	49	117	1606	104
2.85	461	494	47	116	1544	100
2.90	444	472	46	115	1498	97
2.95	429	454	45	115	1452	94
3.00	415	437	44	114	1405	91
3.05	401	420	42	113	1359	88
3.10	388	404	41	112	1297	84
3.15	375	389	40	112	1266	82
3.20	363	375	38	110	1220	79
3.25	352	363	37	110	1174	76
3.30	341	350	36	109	1143	74
3.35	331	339	35	109	1112	72
3.40	321	327	34	108	1081	70
3.45	311	316	33	108	1050	68
3.50	302	305	32	107	1019	66
3.55	293	296	31	106	988	64
3.60	285	287	30	105	958	62
3.65	277	279	29	104	927	60
3.70	269	270	28	104	911	59
3.75	262	263	26	103	880	57
3.80	255	256	25	102	849	55
3.85	248	248	24	102	834	54
3.90	241	241	23	100	803	52
3.95	235	235	22	99	788	51
4.00	229	229	21	98	772	50
4.05	223	223	20	97	757	49
4.10	217	217	18	96	726	47
4.15	212	212	17	96	710	46
4.20	207	207	16	95	695	45
4.25	201	202	15	94	680	44
4.30	197	197	13	93	664	43
4.35	192	192	12	92	649	42
4.40	187	187	10	91	633	41
4.45	183	183	9	90	618	40
4.50	179	179	8	89	610	39.5
4.55	174	174	7	88	602	39
4.60	170	170	6	87	595	38.5
4.65	167	166	4	86	587	38
4.70	163	163	3	85	579	37.5
4.75	159	159	2	84	564	36.5
4.80	156	156	1	83	556	36
4.85	152	153	0	82	541	35
4.90	149	149	-1	81	525	34
4.95	146	146	-2	80	517	33.5
5.00	143	143	-3	79	510	33
5.05	140	140	-4	78	494	32
5.10	137	137	-6	77	486	31.5
5.15	134	134	-7	76	479	31
5.20	131	131	-9	74	463	30
5.25	128	128	-11	73	456	29.5
5.30	126	126	-12	72	448	29
5.35	123	124	-14	71	440	28.5
5.40	121	121	-16	70	432	28
5.45	118	118	-17	69	417	27
5.50	116	116	-19	68	409	26.5
5.55	114	114	-20	67	402	26
5.60	111	112	–	66	394	25.5
5.65	109	109	–	65	386	25
5.70	107	107	–	64	378	24.5
5.75	105	105	–	62	371	24
5.80	103	103	–	61	363	23.5
5.85	101	101	–	60	355	23
5.90	99.2	99	–	59	351	22.75
5.95	97.3	97	–	57	347	22.5
6.00	95.5	95	–	56	340	22

The equivalents given are approximations and must not be accepted as rigid. Certain conditions, especially the incidence of cold work, can alter the relation between hardness and tensile strength profoundly. The hardness systems, given above, are in general use in industry, and it is convenient to be able to translate the results of one in terms of the hardness units of the other. The table is offered as a guide only, and should be used with due discretion.