Hardness Scale & Conversions

At Blackalloy Company of America, use our comprehensive guide hardness scales and conversions to understand the various methods used to measure material hardness. Hardness testing is crucial in material selection, ensuring that components can withstand the demands of their intended applications. Browse the table below to find more information on the different hardness scales, including the Rockwell hardness chart, the Brinell hardness chart for metals and the distinctions between the Rockwell hardness scale B vs. C, while also offering insights into how to convert between these scales for accurate comparisons.

Whether you're an engineer, manufacturer, or simply interested in the properties of materials, or simply need further insights into the meta hardness scale to evaluate and compare materials effectively, this article will equip you with the knowledge needed to effectively assess and select the right materials for your projects.

Brinell Hardness - Used for determining the hardness of metals. This hardness scale is often used for steel parts and comparative conversions between Brinell and Rockwell scales. The comparative scales are listed in the chart below.
Rockwell Hardness - Probably the most familiar hardness measurement technique because of its' wide range. Useful for measuring many materials from soft bearing metals to carbides. The different Rockwell scales are listed in the chart below.
Shore's Hardness - a common scale for elastic materials such as rubber and plastics.
Vicker's Hardness - useful for thin materials.
Knoop Hardness - a test applicable to thin materials, plated surfaces, exceptionally hard and brittle materials and shallow hardened surfaces such as surfaces nitrided or carburized.

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Hardness Conversion Chart
Brinell Hardness	Rockwell Hardness
Brinell Hardness	A Scale	B Scale	C Scale
--	85.6	--	68.0
--	85.3	--	67.5
--	85.0	--	67.0
767	84.7	--	66.4
757	84.4	--	65.9
745	84.1	--	65.3
733	83.8	--	64.7
722	83.4	--	64.0
712	--	--	--
710	83.0	--	63.3
698	82.6	--	62.5
684	82.2	--	61.8
682	82.2	--	61.7
670	81.8	--	61.0
656	81.3	--	60.1
653	81.2	--	60.0
647	81.1	--	59.7
638	80.8	--	59.2
630	80.6	--	58.8
627	80.5	--	58.7
601	79.8	--	57.3
578	79.1	--	56.0
555	78.4	--	54.7
534	77.8	--	53.5
514	76.9	--	52.1
495	76.3	--	51.0
477	75.6	--	49.6
461	74.9	--	48.5
444	74.2	--	47.1
429	73.4	--	45.7
415	72.8	--	44.5
401	72.0	--	43.1
388	71.4	--	41.8
375	70.6	--	40.4
363	70.0	--	39.1
352	69.3	--	37.9
341	68.7	--	36.6

Brinell Hardness	Rockwell Hardness
Brinell Hardness	A Scale	B Scale	C Scale
331	68.1	--	35.5
321	67.5	--	34.3
311	66.9	--	33.1
302	66.3	--	32.1
293	65.7	--	30.9
285	65.3	--	29.9
277	64.6	--	28.8
269	64.1	--	27.6
262	63.6	--	26.6
255	63.0	--	25.4
248	62.5	--	24.2
241	61.8	100.0	22.8
235	61.4	99.0	21.7
229	60.8	98.2	20.5
223	--	97.3	20.0
217	--	96.4	18.0
212	--	95.5	17.0
207	--	94.6	16.0
201	--	93.8	15.0
197	--	92.8	--
192	--	91.9	--
187	--	90.7	--
183	--	90.0	--
179	--	89.0	--
174	--	87.8	--
170	--	86.8	--
167	--	86.0	--
163	--	85.0	--
156	--	82.9	--
149	--	80.8	--
143	--	78.7	--
137	--	76.4	--
131	--	74.0	--
126	--	72.0	--
121	--	69.8	--
116	--	67.6	--
111	--	65.7	--

Hardness Scale & Conversions

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