25ХГМ - GOST 4543-1971

Grade	25ХГМ
Corresponding Standard	GOST 4543-1971 Alloyed Construction Steel Specifications
Classification	Alloy Steel
Properties	High Hardenability

25ХГМ Chemical Element Composition Content (%)

Component	C	Si	Mn	P	S	Cr	Ni	Cu	Mo
Minimum Value	0.23	0.17	0.9	-	-	0.9	-	-	0.2
Maximum Value	0.29	0.37	1.2	0.035	0.035	1.2	0.3	0.3	0.3

• 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.

25ХГМ Mechanical Properties

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
Quenching 880°C oil cooling, Tempering 500°C air cooling	≥1180	≥1060	≥10	≥45	Impact energy per unit area KCU: ≥78J/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

Approximate Comparison Table Hardenability Guaranteed Structural Steel

China		United States		International Organization for Standardization	Germany		France	Russia	United Kingdom
GB	ISC	ASTM	UNS	ISO	DIN EN/DIN	W-Nr.	NF EN/NF	GOST	BS EN/BS
20CrMnMoH	A34205	4118H	H41180	20MnCr5H	≈20MnCr5	≈1.7147	(20MC5H)	25ХГМ	(708H20)

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