Metallic Material Hardness Testing and Steel Hardness Comparison Table

The ability of metal materials to resist the surface indentation of hard objects. It is called hardness. According to different testing methods and applicable ranges, hardness can be divided into Brinell hardness, Rockwell hardness, Vickers hardness, Shore hardness, and microhardness

And high temperature hardness, etc. For pipes, there are generally three commonly used degrees: Brinell, Rockwell, and Vickers.

A. Brinell hardness (HB)

Press a steel ball or hard alloy ball of a certain diameter into the surface of the specimen with a specified test force (F), and after a specified holding time, remove the test force and measure the indentation diameter (L) on the surface of the specimen. The Brinell hardness value is measured by the test force

The quotient obtained by dividing by the surface area of the indentation sphere. Expressed in HBS (steel ball), the unit is W/mm2 (MPa).

B. Rockwell hardness (HR)

The Rockwell hardness test, like the Brinell hardness test, is an indentation test method. Differently, it measures the depth of the indentation. That is, under the successive action of the initial test force (F0) and the total test force (F), the indenter (steel mill cone or steel ball) is pressed into the surface of the specimen, and after a specified holding time, the main test force is removed, and the hardness value is calculated using the measured residual indentation depth increment (e). Its value is an unnamed number, represented by symbols, and there are 9 scales used, including A, B, C, D, E, F, G, H, K, etc. The commonly used scales for steel hardness testing are generally A, B, and C, namely HRA, HRB, and HRC. The Rockwell hardness test is currently a widely used method, among which the use of C in steel pipe standards is second only to Brinell hardness. Rockwell hardness can be used to determine metal materials ranging from extremely soft to extremely hard, which makes up for the inconvenience of the Brinell method and is simpler than the Brinell method. The hardness value can be directly read from the dial of the hardness machine. However, due to its small indentation, the hardness value is not as accurate as the Brinell method.

C. Vickers hardness (HV)

The Vickers hardness test is also an indentation test method, which involves pressing a regular square pyramid diamond indenter with a relative angle of 1360 into the test surface with a selected test force (F), and removing the test force after a specified holding time,

Measure the length of the two diagonal lines of the indentation.

With the improvement of hardness tester manufacturing technology, various portable instruments, especially high-precision portable instruments, continue to emerge, making hardness testing simple, fast, and accurate. Enable on-site hardness testing, hardness control on production lines, and accurate hardness testing of large workpieces.

List Of Commonly Used Steel Heat Treatment Hardness

Steel Grade	Reference Diameter And Thickness	Recommended Hardness		Notes
Steel Grade	Reference Diameter And Thickness	HB	Indentation Diameter	Notes
35	φ≤10	388-321	3.1-3.4
	φ≤20	321-269	3.4-3.7
	φ30-φ40	285-229	3.6-4.0
	Thickness ≤ 20 Plate	269-217	3.7-4.1
	Thickness ≤ 40	229-187	4.0-4.4
40	φ≤25	388-321	3.1-3.4	Surface quenching hardness HRC ≥ 38
	φ≤40	321-269	3.4-3.7
	φ≤50	285-229	3.6-4.0
	Thickness ≤ 20 Plate	284-241	3.6-3.9
	Thickness ≤ 40	241-207	3.9-4.2
45	φ≤25	477-388	2.8-3.1	Surface quenching hardness： When φ≥100,HRC≥40；When φ≤100,HRC≥45 HRC≥48；
	φ≤40	388-321	3.1-3.4
	φ≤60	321-269	3.4-3.7
	φ≤75	285-229	3.6-4.0
	Thickness ≤ 20 Plate	321-269	3.4-3.7
	Thickness ≤ 40 Plate	285-229	3.6-4.0
	Thickness ≤ 60 Plate	241-207	3.9-4.2
50	φ≤40	477-388	2.8-3.1
40Cr 30CrMoA 35CrMo 40Mn2	φ≤30	477-388	2.8-3.1	Surface quenching hardness HRC ≥ 45
	φ≤50	388-321	3.1-3.4
	φ≤80	321-269
	φ≤120	285-229

Alloy Cast Steel

Steel Grade	Recommended Hardness Range
Steel Grade	Brinell Hardness HB	Indentation Diameter
ZG32MnMo ZG32MnMo1	321-269	3.4-3.7
	285-241	3.6-3.9
	255-217	3.8-4.1

Cast Steel

Steel Grade	Recommended Hardness Range
Steel Grade	Brinell Hardness HB	Indentation Diameter
ZG35(ZG270-500) ZG45(ZG310-570) ZG55(ZG340-640)	Refer to carbon steel in carbon medium	Refer to carbon steel in carbon medium

Alloy Carburizing Steel

Steel Grade	Modulus m Infiltration	Thickness Of Carburized Layer mm	Surface Hardness HRC	Core Hardness HRC
12CrNi3A	3.0-4.5	0.6-0.9	≥58	26-40
12CrNi3A	1.75-2.5	0.5-0.7	≥54	26-40
18CrNi4WA	2.75-3.85	0.7-1.0	≥54
	4.5	0.8-1.1	≥56
	bevel gear m≥7.72	0.8-1.1	≥56	35-45
	bevel gear m≥7.72	0.8-1.2	≥54	35-45
20Cr2Ni4A (12Cr2Ni4A)	5-5.5	1.4-1.7	≥60	35-49 12Cr2Ni4A: 35-45
	5-5.5	1.3-1.6	≥60
	7	1.3-1.7	≥60
	8-9	1.3-1.7	≥60
		1.6-1.9
		1.5-1.8
20CrMnTi	3.5-4.5	0.9-1.3	58-63	33-48

High Carbon Chromium Bearing Steel

Steel Grade	Recommended Hardness
GCr15	HRC≥58
GCr9	HRC≥58

Carbonitriding

Steel Grade	Modulus m Infiltration	Thickness Of Carburized Layer mm	Surface Hardness HRC
12CrNi3A 20CrMnTi 20Cr	＜4	0.5-0.8	≥56
12CrNi3A 20CrMnTi 20Cr	4-6	≥0.6	≥56
20Cr2Ni4A 12Cr2Ni4A 30CrMnTi	＜4	0.5-0.8	≥58
20Cr2Ni4A 12Cr2Ni4A 30CrMnTi	4-6	≥6	≥58
20Cr2Ni4A 12Cr2Ni4A 30CrMnTi	≥7	0.7-0.8	≥58
Steel Grade	Recommended hardness HB	Notes
18Cr2Ni4WA 20Cr2Ni4A	375-311	18Cr2Ni4WA can manufacture engine crankshafts, transmissions, main shafts, passive shafts, etc 20Cr2Ni4A can be used to produce gears, etc
	444-341
	444-321
Steel Grade	Reference Diameter And Thickness	Recommended Hardness	Notes
Steel Grade	Reference Diameter And Thickness	HB	Notes
38CrSi 42CrMo 45CrNi	φ≤30	477-388	Surface quenching hardness HRC≥42 HRC≥45 HRC≥48
	Gear Class	415-341
	Toothed Hair Orchid Disc	388-321
	φ≤80	341-285
	φ≤100	321-269
	φ≤120	302-255
	φ≥120	285-229
30CrMnSiA		388-302	Gaskets, etc
35CrMnSiA		321-269	Friction plates, etc
35CrMnSiA		285-241	Bucket holder

Stainless Steel

Steel Grade	Recommended Hardness HB	Notes
2Cr13	302-255
3Cr13	341-285	Surface quenching hardness: Support bushing HRC≥50
4Cr13	285-355	Surface quenching hardness: Support bushing HRC≥50

Spring Steel

Steel Grade	Recommended Hardness HB	Notes
65		Cold hard steel wire with a diameter of less than 6
70		Cold hard steel wire with a diameter of less than 6
85	36-42	Generally used for small section spring sheets or washers with a thickness of no more than 15
	38-48
	47-54
60Mn	36-42	Manufacturing large-sized springs/leaf springs/mainsprings/* *, etc
60Mn	40-48
65Mn	42-50	Manufacturing large-sized springs
60Si2Mn 60SiMnA	41-49	Suitable for leaf springs
60SiMnWA	41-49	Large section heavy-duty spring
70Si3MnA	44-52	Large section heavy-duty spring
50CrVA	40-48	Large section heavy-duty spring Springs working below 300 ℃
50CrVA	42-50	Large section heavy-duty spring Springs working below 300 ℃
45CrNiMoVA	41-47	Elastic shaft type
60si2CrV 50CrMnVA 55SiMnMo V55SiMnMoB	45-52	Large section heavy-duty spring

Reference Table For Hardness Of Common Materials

Type	Material	State	Hardness	Notes
Lathe Material	Iron material	1/2H	HV210-240
	stainless steel	1/2H	HB<=262
	copper	1/2H	HV＞=80
	aluminium	1/2H
Screw Material	Iron material	Soft material	HV120-180	HRB<95
	Stainless steel 302	Soft material	HB88-96
	stainless steel 304	1/2H	HB150-180
	copper	Soft material
	aluminium	Soft material
Axle material	Iron material
Axle material	stainless steel
Stamping material	Iron material SPCC	1/8H	HV95-130
		1/4H	HV115-150
		1/2H	HV135-185
		H	HV>170
		Annealing A	HV<105
		Quenching and tempering S	HV<115
	MANGANESE FLAKE SK5	Soft material	HV150-170
		1/2H	HV220-250
		H	HV450-500
	Stainless steel SUS301	1/4H	HV270-290
		1/2H	HV310-330
		3/4H	HV370-390
		H	HV430-450
		EH	HV490-520
	stainless steel SUS304	1/4H	HV<210
		1/2H	HV270-290
		3/4H	HV310-330
		H	HV370-390
	brass H65-H70	1/4H	HV75-125
		1/2H	HV85-145
		H	HV105-175
		EH	HV145 MIN
	Phosphor bronze C5191	1/4H	HV100-160
		1/2H	HV150-205
		H	HV180-230
		EH	HV200 MIN
	ALUMINUM A1100	0	HV20
		Hx2	HV30
		Hx4	HV36
		Hx6	-
		Hx8	HV44
		Hx9	HV51
	aluminum alloy A5052	0	HV50
		Hx2	HV70
		Hx4	HV75
		Hx6	HV80
		Hx8	HV85
		Hx9	HV95

Table Of Heat Treatment Parameters For Common Materials

Steel Grade			Quenching	Carburization			Nitridation
NO	China	Japan	Hardness（HRC）	Surface hardness (HRC) (normal lower limit value)	Thickness of carburized layer (mm) Thickness: 0.05/1H	Unilateral size change (mm)	Surface hardness (HRC) (normal lower limit value)	Thickness of nitride layer (mm) Thickness: 0.01mm/1H	Unilateral size change (mm)
1	10	S10C	25	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
2	45	S45C	45~50	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
3	65Mn		59~61	≥60	No need to do it		feasible	normal 0.15~0.2	≤0.01mm
4	T8	SK6,SK5	60~63	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
5	T10	SK3,SK4	60~63	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
6	Cr12	SKD1	60~64	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
7	Cr12MoV	SKD11	60~64	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
8	9CrWMn	SKS3	60~64	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
9	W18Cr4V	SKH2	62~65	≥60	normal0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
10	W6Mo5Cr4V2	SKH9	63~66	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
11	Y1Cr18Ni9	SUS303	Austenitic stainless steel, cannot be heat treated for hardening	Cannot do it			Special treatment nitriding (glow plasma nitriding)
12	0Cr19Ni9	SUS304	Austenitic stainless steel, cannot be heat treated for hardening	Cannot do it			Special treatment nitriding (glow plasma nitriding)
13	1Cr13	SUS410	＜48	≥60	normal 0.3-0.5	≥0.1mm	≥700	≥0.1-0.5	≤0.01mm
14	0Cr17Ni12Mo2	SUS316	Austenitic stainless steel, cannot be heat treated for hardening	Cannot do it			Special treatment nitriding (glow plasma nitriding)
15	9Cr18	SUS440C	≥60	≥60	No need to do it		≥700	normal 0.15~0.2	≤0.01mm
16	4Cr13	SUS420J2 (S136H Sweden)	60-63	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm
17	Q235A	SS400	≤35	≥60	normal 0.3-0.5	≥0.1mm	≥600	normal 0.15~0.2	≤0.01mm

Common Steel Hardness Table

Steels	Hardness（HRC）	Hardness after quenching（HRC）
S50C	23°	46-48°
P20	30-32°	-
738	30-33°	Can be used for surface nitriding
718	31-33°	48-52°
SKD61	20-22°	48-52°
8407 2M	20-22°	48-52°
S136	20-22°	48-52°
NAK80	39-41°	Can be used for surface nitriding
DC53	20-22°	60-61°
SKD11	20-22°	58-60°
VIKING		52-54°

Common Hardware Material Hardness Table

Name	Code	Hardness(HV)	Notes
Electrolytic material	SECC	90-110
Single light material	SPCC-SD	85-100
Double gloss material	SPCC-SB	130-150
Phosphor bronze	PBS	C5210 1/2H 120-195
Phosphor bronze		C5210H 170-220
bronze	BSP	C2680 1/2H 85-145
bronze	BSP	C2680 H 105-175
stainless steel	SUS304-CSP	1/2H 250-300
	SUS304-CSP	¾H310-370H370 above
	SUS301-CSP	1/2H310-380	Easy to rust
	SUS301-CSP	¾H370-410 H420	Easy to rust
Environmentally friendly stainless steel	SUS316	130-170
aluminum alloy	AL5052-H34	70-80
aluminum alloy	AL1100	39-41
galvanized iron	SPTE	100
Zinc iron material	SGCC	100-125

Japanese Standard Hardness Table For Carbon Steel And Alloy Steel Materials

JIS	AISI Or SAE	Chemical Composition % (maxima unless stated )								Mechanical Proporties (minima unless stated )
		C	Si	Mn	P	S	Cr	Mo	Ni	Yield strength	Tensile strength	Elongation	Impact	Hardness
		C	Si	Mn	P	S	Cr	Mo	Ni	kg/mm2	kg/mm2	%	J	HB
Carbon Steel for Machine Stuctural Use JiS G4051 :1979
S10C		0.08~0.13	0.15~0.35	0.30~0.60	0.03	0.035	-	-	-	21	32	33	-	109-159
	1010	0.08~0.13	-	0.30~0.60	0.035	0.045	-	-	-	21	32	33	-	109-159
S15C		0.13~0.18	0.15~0.35	0.30~0.60	0.03	0.035	-	-	-	24	38	30	-	111-167
	1015	0.13~0.18	-	0.30~0.60	0.035	0.045	-	-	-	24	38	30	-	111-167
S20C		0.18~0.23	0.15~0.35	0.30~0.60	0.03	0.035	-	-	-	35	41	28	-	116-174
	1020	0.18~0.23	-	0.30~0.60	0.035	0.045	-	-	-	35	41	28	-	116-174
S40C		0.37~0.43	0.15~0.35	0.60~0.90	0.03	0.035	-	-	-	33	55	22	-	156-217
	1040	0.37~0.44	-	0.60~0.90	0.03	0.035	-	-	-	33	55	22	-	156-217
S45C		0.42~0.48	0.15~0.35	0.60~0.90	0.03	0.035	-	-	-	35	58	20	-	167-229
	1045	0.43~0.50	-	0.60~0.90	0.03	0.045	-	-	-	35	58	20	-	167-229
S55C		0.52-0.58	0.15-0.35	0.60-0.90	0.03	0.035	-	-	-	40	66	15	-	183-255
	1055	0.50-0.60	-	0.60-0.90	0.035	0.045	-	-	-	40	66	15	-	183-255
Chromium Molybdenum Steels JlS G4105 :1979
SCM430		0.28-0.33	0.15-0.35	0.60-0.85	0.03	0.03	0.90-1.20	0.15-0.30	-	70	85	18	11	241-293
	4130	0.28-0.33	0.15-0.35	0.40-0.60	0.035	0.04	0.80-1.10	0.15-0.25	-	70	85	18	11	241-293
SCM440		0.38-0.43	0.15-0.35	0.60-0.85	0.03	0.03	0.90-1.20	0.15-0.30	-	85	100	12	6	285-341
	4140	0.38-0.43	0.15-0.30	0.75-1.00	0.035	0.04	0.80-1.10	0.15-0.25	-	85	100	12	6	285-341
Nickel Chromium Molybdenum SteelsJlS G4103 :1979
SNCM420		0.17-0.23	0.15-0.35	0.40-0.70	0.03	0.03	0.40-0.65	0.15-0.30	1.60-2.00	-	100	15	7	293-375
	4320	0.17-0.22	0.15-0.30	0.45-0.65	0.035	0.04	0.40-0.60	0.20-0.30	1.65-2.00	-	100	15	7	293-375
SNCM439		0.36-0.43	0.15-0.35	0.60-0.90	0.03	0.03	0.60-1.00	0.15-0.30	1.60-2.00	90	100	16	7	293-352
	4340	0.38-0.43	0.15-0.30	0.60-0.80	0.035	0.03	0.70-0.90	0.20-0.30	1.65-2.00	90	100	16	7	293-352