4140 Alloy Round Bar

Supply Range

4140 Steel Round Bar: diameter 8mm – 3000mm
4140 Steel Plate: thickness 10mm – 1500mm x width 200mm – 3000mm
4140 Steel Grade Square: 20mm – 500mm

Common 4140 Steel Specifications

Country	USA	German	British	Japan	China	Australia
Standard	ASTM A29	DIN 17200	BS 970	JIS G4105	GB/T 3077	AS 1444
Grades	4140	1.7225/42CRMO4	42CrMo4	SCM440	42CrMo	4140

SAE 4140 Carbon Steel Round Bar Chemical Composition

	Min. %	Max %
Carbon	0.36	0.44
Silicon	0.10	0.40
Manganese	0.65	1.10
Chromium	0.75	1.20
Molybdenum	0.15	0.35
Phosphorous	0	0.04
Sulphur	0	0.04

SAE 4140 Carbon Steel Round Bar Physical Properties

Physical Properties	Metric	Imperial
Density	7.85 g/cm3	0.284 lb/in3

SAE 4140 Carbon Steel Round Bar Mechanical Properties

Mechanical Property Designation		R	S	S	*T	U	V	W
Limited Ruling Section mm		250	250	150	100	63	30	20
Tensile Strength Mpa	Min	700	770	770	850	930	1000	1080
Tensile Strength Mpa	Max	850	930	930	1000	1080	1150	1230
0.2% Proof Stress Mpa	Min	480	540	570	655	740	835	925
Elongation on 5.65√S0 %	Min	15	13	15	13	12	12	12
Izod Impact J	Min	34	27	54	54	47	47	40
Charpy Impact J	Min	28	22	50	50	42	42	35
Hardness Brinell HB	Min	201	233	233	248	269	293	311
Hardness Brinell HB	Max	255	277	277	302	331	352	375