40ХФА - GOST 4543-1971

Grade	40ХФА
Corresponding Standard	GOST 4543-1971 Alloyed Construction Steel Specifications
Classification	Alloy Steel
Properties	High Hardenability

40ХФА Chemical Element Composition Content (%)

Component	C	Si	Mn	P	S	Cr	Ni	Cu	V
Minimum Value	0.37	0.17	0.5	-	-	0.8	-	-	0.1
Maximum Value	0.44	0.37	0.8	0.025	0.025	1.1	0.3	0.3	0.18

• The letter A at the end of the grade stands for “high quality steel”. Character III means “Extra high quality steel”. For example, quality steel -30XΓC; High quality steel -30XΓCA; Extra high quality steel -30X ΓC-Ⅲ and 30XΓCA-Ⅲ.

40ХФА Mechanical Properties

diameter(thickness) d(t) mm	Heat Treatment or Condition	Tensile Strength σ_b Mpa	Yield Point σ_s Mpa	Elongation or Extension Rate δ %	Reduction of Area ψ %	Impact Energy Absorption KV2 J
d=25	Quenching + Tempering	≥880	≥735	≥10	≥50	KCU: ≥88J/cm2

• d=circle diameter or quadrate side，unit mm
• Mechanical properties suitable for diameter or thickness less than or equal to 80mm, other sizes of mechanical properties requirements see the standard original.
• The impact test shall comply with GOST 9454-78.
• If the yield phenomenon is not obvious and the yield stress σT(i.e., σs) cannot be determined, the yield limit σ0.2(i.e., Rp0.2) is allowed.
• Allowable deviation of heat treatment temperature: quenching ±15°C; Low temperature tempering ±30°C; High temperature tempering ±50°C

◎ Heat treatment: Quenching Temperature 880°C, Oil cooling；Tempering Temperature 650°C，water or oil cooling.

Approximate Comparison Table Structural Alloy Steel

Japan	United States		Germany		France	European Standard	Russia	United Kingdom
JIS	ASTM/AISI	UNS	DIN EN/DIN	W-Nr.	NF EN/NF	EN	GOST	BS EN/BS
SCM440	4140 4142 6135	G41400	41CrMo4	1.7223	42CD4TS	41CrMo	40ХФА 40KHFA	3111-5/1 42CrMo4 708M40

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