Steel 16Х20К6Н2МВФ (ЭП768; VNS-22)

Designation

Name The value
Designation GOST Cyrillic 16Х20К6Н2МВФ
Designation GOST Latin 16X20K6H2MBF
Transliteration 16H20K6N2MVF
By chemical elements 16Cr20Co6Н2MoWV
Name The value
Designation GOST Cyrillic ЭП768
Designation GOST Latin EP768
Transliteration EhP768
By chemical elements -
Name The value
Designation GOST Cyrillic ВНС-22
Designation GOST Latin BHC-22
Transliteration VNS-22
By chemical elements WНС-22

Description

16Х20К6Н2МВФ steel is used: for manufacturing parts of burners, covers thermocouples, furnace parts.

Standards

Name Code Standards
Bars and shapes В32 TU 14-1-957-74

Chemical composition

Standard C S P Mn Cr Si Ni Fe V Mo W Co
TU 14-1-957-74 0.14-0.18 ≤0.02 ≤0.02 ≤0.5 18.5-20.5 ≤0.5 2-2.5 Rest 0.18-0.3 1.1-1.4 0.3-0.6 5.5-6.5
Fe is the basis.
According to TU 14-1-957-74, the chemical composition is given for steel grade 16Х20К6Н2МВФ-Ш (ЭП768-Ш). Subject to the requirements of the technical specification, deviations from the chemical composition standards are allowed: carbon ± 0.010%, vanadium ± 0.020%, nickel -0.20%, chromium ± 0.050%, tungsten ± 0.050%, molybdenum + 0.020 / - 0.050%. The steel determines the nitrogen content, the results are recorded in the certificate.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2 HB, MPa
Bars hot rolled and forged on the other 14-1-957-74. Quenching in oil from 1060±10 °C + cold Treatment at minus 70 °C for 2 hours + Vacation at 640±20 °C (extract 3 hours), air cooling (Impact toughness KCV)
20-25 ≥735 ≥980 ≥11 ≥48 ≥590 302-376

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
HB Brinell hardness number

Technological properties

Name The value
Macrostructure and pollution On the other 14-1-957-74 the macrostructure of the steel on the etched transverse templeto should not be visible without using the magnifying devices of the traces of shrinkage, cracks, delamination, inclusions, subcortical bubbles and intergranular cracks, voids, fistula. On microtemplate evaluates the following types of defects and their number allowed: Central porosity ≤ 1 point; - at the point of heterogeneity of ≤ 1 point; - in General spotty liquation ≤ 1 point; - phase separation to the square of the ≤ 1 point; - for layer-by-layer crystallization and the bright contour of ≤ 3 points. The remaining defects are classified GOST 10243 are not allowed. Rules of macrostructure in points to be advised after delivery at least 20 heats. Evaluation of contamination of metal non-metallic inclusions is made at the scales GOST 1778 by: - stroke oxides; silicates fragile; the point oxides; silicates plastic; - silicates, non-deformed; - sulphides. Actual results of assessment of pollution in points are recorded in the certificate.
Particularities of production of goods Bars hot rolled and forged on the other 14-1-957-74 supplied heat-treated with hardness not more than 341 HB (indentation diameter of not less than 3,30 mm).