L7M L70 - ASTM A 320-2000

AISI American Iron and Steel Institute	4140
ASTM Specification or Grade	L7
Other Names
Corresponding Standard	ASTM A 320-2000
Classification	Alloy Steel
Properties	Strength Quench Hardness

Chemical Element Composition Content (%)

Component	C	Si	Mn	P	S	Cr	Mo
Minimum Value	0.38	0.15	0.75	-	-	0.8	0.15
Maximum Value	0.43	0.35	1	0.035	0.04	1.1	0.25

Mechanical Properties

diameter（grade） d mm	Heat Treatment or Condition	Tensile Strength σ_b Mpa	Yield Point σ_s Mpa	Elongation or Extension Rate δ %
d≤65(L7、L70)	Quenching + Tempering	≥860	≥725	≥16
d≤65(L7M)		≥690	≥550

1 Approximate Comparison Table

United States	International Organization for Standardization	Germany	France	European Standard
ASTM	ISO	DIN EN/DIN	NF EN/NF	EN	Numerical Grade
4140	42CrMoS4	42CrMoS4	42CD4u	42CrMoS4	1.7227

2 Approximate Comparison Table structural alloy steel

China	Japan	United States	International Organization for Standardization	Germany	France	European Standard		Russia	Sweden	United Kingdom
GB	JIS	ASTM	ISO	DIN EN/DIN	NF EN/NF	EN	Numerical Grade	GOST	SS	BS EN/BS
42CrMo	SCM440H	4140 4142	42CrMo4	42CrMo4	42CD4	42CrMo4	1.7225	35KHM 38KHM	2244	708M40 CFS11

3 Approximate Comparison Table structural alloy steel

Note: The data is for reference only! If you have any questions, please fill out "I want to correct it"!