Steel 40ХН2СВА (ЭИ643)

Designation

Name The value
Designation GOST Cyrillic 40ХН2СВА
Designation GOST Latin 40XH2CBA
Transliteration 40HN2SVA
By chemical elements 40CrН2СW
Name The value
Designation GOST Cyrillic ЭИ643
Designation GOST Latin EI643
Transliteration EhI643
By chemical elements -

Description

40ХН2СВА steel is used: for the manufacture of hot-rolled bars, forgings, seamless pipes and fittings chemical engineering and special equipment.

Note

High-strength steel. When you replace the vanadium-molybdenum steel is marked 40ХН2СМА (EI643M).

Standards

Name Code Standards
Classification, nomenclature and General rules В20 OST 1 90005-91
Blanks. Of the workpiece. Slabs В31 TU 1-92-156-90
Bars and shapes В32 TU 14-1-313-72
Steel pipes and fittings to them В62 TU 14-3-170-73

Chemical composition

Standard C S P Mn Cr Si Ni Fe Mo W
TU 14-1-313-72 0.36-0.42 ≤0.025 ≤0.025 0.5-0.8 0.8-1.1 0.7-1 2.5-3 Rest ≤0.15 0.8-1.2
Fe is the basis.
According to TU 14-1-313-72, the chemical composition is given for steel 40ХН2СВА (ЭИ643). The mass fraction of residual copper in steel should not exceed 0.25%. In the steel grade 40HN2SVA (EI643), partial replacement of tungsten with molybdenum is allowed, at the rate of three weight parts of tungsten is replaced by one part by weight of molybdenum. In bars and forgings, subject to other requirements, deviations from the chemical composition standards for carbon are allowed: + 0.010%, for manganese - ± 0.050%, for chromium ± 0.10%, for nickel ± 0.10%, for tungsten - ± 0.10%, molybdenum - + 0.050%.

Mechanical properties

Section, mm σU, MPa d5, % y, % KCU, kJ/m2 HB, MPa
Long products and forgings on the other 1-92-156-90 (TU 14-1-313-72). Quenching in oil with 890-910 °C + Vacation at 200-260 (200-300) °C, air cooling
≥1860 ≥8 ≥35 ≥590 ≤514

Description mechanical marks

Name Description
σU Limit short-term strength
d5 Elongation after rupture
y The relative narrowing
KCU Toughness
HB Brinell hardness number

Technological properties

Name The value
Features of heat treatment Bars and forgings on the other 14-1-313-72 put after the heat treatment (low annealing), hardness Brinell hardness no more than 269НВ (indentation diameter not less than 3.7 mm). Recommended low mode annealing: heating to a temperature of 650-680 °C, exposure time 12 hours, air cooling. Forgings to low annealing subjected to preliminary normalization with a temperature of 900 °C.