Steel 25ХН3МФА (25ХН3МФАР)

Designation

Name The value
Designation GOST Cyrillic 25ХН3МФА
Designation GOST Latin 25XH3MFA
Transliteration 25HN3MFA
By chemical elements 25CrН3MoV
Name The value
Designation GOST Cyrillic 25ХН3МФАР
Designation GOST Latin 25XH3MFAP
Transliteration 25HN3MFAR
By chemical elements 25CrН3MoVNB

Description

25ХН3МФА steel is used: for the manufacture of forgings of various parts of General engineering; billets of shafts of gas turbine rotors and turbine generators; backup rolls of rolling mills.

Standards

Name Code Standards
Blanks. Of the workpiece. Slabs В31 TU 108.11.943-87, TU 108.11.945-87
Processing of metals by pressure. Forgings В03 TU 3-896-78, TU 108.11.931-87, TU 108-11-38-76, TU 108.11.917-87

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Mo
TU 3-896-78 0.22-0.3 ≤0.025 ≤0.025 0.25-0.5 1.4-1.8 0.17-0.37 3-3.75 Rest ≤0.2 0.08-0.15 0.3-0.5
TU 108.11.917-87 0.2-0.25 ≤0.02 ≤0.02 0.25-0.5 1.4-1.8 ≤0.37 3-3.75 Rest ≤0.3 0.08-0.15 0.3-0.5
Fe is the basis.
According to TU 3-896-78 the chemical composition is given for the rotary grade steel 25ХН3МФАР.
According to TU 108.11.917-87 the chemical composition is given for steel grade 25ХН3МФА. The total content of phosphorus and sulfur should be ≤ 0.035%. According to TU 108.11.917-87, after processing the steel on the OSRV, a limitation on the sulfur content ≤ 0.015% and phosphorus ≤ 0.015% is introduced. The total content of sulfur and phosphorus after OSRV ≤ 0.020%.

Mechanical properties

sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2
Forged billet rotors of turbine generators, thermal power plants up to 500 MW III-VI categories on the other 3-896-78 (indicate the cutting direction of sample)
≥540 ≥687 ≥19 ≥55 ≥1177
≥540 ≥687 ≥17 ≥45 ≥785
≥638 ≥785 ≥18 ≥55 ≥981
≥638 ≥785 ≥17 ≥45 ≥687

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
y The relative narrowing
KCU Toughness