Steel 25Х3МФА-

Designation

Name	The value
Designation GOST Cyrillic	25Х3МФА-А
Designation GOST Latin	25X3MFA-A
Transliteration	25H3MFA-A
By chemical elements	25Cr3MoVN-

Description

Steel 25Х3МФА AND used: for the production of workpieces in the form of forgings, sheets, sheet blanks, the sheet of stamped blanks, Cavanaugh-rolled billets (slabs), used for products of machinery and vessels, working under pressure and within the jurisdiction of the Gosatomenergonadzor.

Standards

Name	Code	Standards
Blanks. Of the workpiece. Slabs	В31	TU 108.131-86

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	As	V	Mo	Sn	Sb	Co
TU 108.131-86	0.22-0.27	≤0.015	≤0.012	0.3-0.6	2.8-3.3	0.17-0.37	≤0.4	Rest	≤0.1	≤0.01	0.25-0.35	0.6-0.8	≤0.005	≤0.005	≤0.025

Fe is the basis.
According to TU 108.131-86 the chemical composition is given for steel grade 25X3MFA. In the chemical composition, deviations are allowed: for carbon -0.010%, for manganese, silicon, and vanadium ± 0.050% for each chromium ± 0.10%. In steel, the total content of phosphorus, antimony, and tin should not be more than 0.015%. Additional determination of the content of zinc, lead and bismuth is carried out. The results of the determination are not delivery, but are recorded in the certificate.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa
Billet heat-treated in the delivery condition on the other 108.131-86
≤600	≥430	540-735	≥14	≥50	≥490	187-229
≤600	≥390	≥490	≥14	≥50	-	-
≤600	≥430	540-735	≥14	≥50	≥490	187-229
≤600	≥390	≥490	≥14	≥50	-	-

Description mechanical marks

Name	Description
s_T\|s_0,2	Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σ_U	Limit short-term strength
d₅	Elongation after rupture
y	The relative narrowing
KCU	Toughness
HB	Brinell hardness number