07Х12НМФБ steel is used: for the production of forged billets with a diameter of 90−180 mm, used for the manufacture of tubes and tube plates of steam generators and nuclear power plant equipment and power plants, operating in conditions of superheated steam at temperatures up to 550−600 °C.

Note

Steel corrosion resistant low carbon martensitic class.

Standards

Name	Code	Standards
Blanks. Of the workpiece. Slabs	В31	TU 14-1-4092-86

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	N	Al	V	Mo	Nb
TU 14-1-4092-86	0.05-0.08	≤0.02	≤0.02	0.3-0.8	11.5-13	≤0.2	0.8-1.3	Rest	≤0.035	≤0.15	0.05-0.2	0.8-1	0.05-0.2

Fe is the basis.
According to TU 14-1-4092-86, the chemical composition is given for steel grade 07Х12НМФБ (ЧС-80), smelted in a plasma or electric arc furnace. Limit deviations from the chemical composition in the workpiece: carbon +0.010%, chromium-0.50%, nitrogen +0.010%, molybdenum ± 0.050%, silicon +0.10%. The residual content of the elements must comply with GOST 5632. Other deviations from the chemical composition of the steel are agreed with the consumer enterprise. At the customer's request, the steel can be doped with boron no more than 0.0050% by calculation without determining by chemical analysis.

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²
Tubular billet forged on the other 14-1-4092-86. Normalization at 1050±20 °C, air cooling + Vacation at 740±20 °C, air cooling (longitudinal samples)
20-25	≥490	≥638	≥15	≥60	≥1180
20-25	≥343	≥440	≥12	≥55	-

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

Technological properties

Name	The value
Pressure treatment	The degree okowa a tube blank on the other 14-1-4092-86 must be at least 3 for a diameter over 120 mm and at least 5 for diameter to 120 mm, inclusive.
Macrostructure and pollution	The macrostructure of billets on the other 14-1-4092-86 should not be visible without using the magnifying devices podnasadochnogo looseness, cracks, foreign non-metallic inclusions, subcortical bubbles and delamination. The defects allowed must not exceed: - for a point heterogeneity - 2 points; - for Central porosity - 2 points; - phase separation in the square - 2 points; - podsadecki segregation - 1 grade. Contamination of billets non-metallic inclusions in the evaluation by the maximum score shall not exceed: - sulphides (C) - 3.0 points; -oxides of stroke (OS) - 4.0 points; - point oxides (FROM) - 3.0 points; - silicates fragile (CX) - 3.0 points; - silicates plastic (SP) - 3.0 points; - silicates, non-deformed (CH) - 3.0 points; - nitrides and carbonitrides stroke (NA) - 3.0 points; - nitrides and carbonitrides point (NT) and 3.0.
Corrosion resistance	Increased resistance to pitting corrosion.

Steel 07Х12НМФБ (ЧС80)

Designation

Description