Steel 03Х9К14Н6М3Д (ЭП921; 03Х9К14Н6М3ДФ)

Designation

Name The value
Designation GOST Cyrillic 03Х9К14Н6М3Д
Designation GOST Latin 03X9K14H6M3D
Transliteration 03H9K14N6M3D
By chemical elements 03Cr9Co14Н6Mo3Cu
Name The value
Designation GOST Cyrillic ЭП921
Designation GOST Latin EP921
Transliteration EhP921
By chemical elements -
Name The value
Designation GOST Cyrillic 03Х9К14Н6М3ДФ
Designation GOST Latin 03X9K14H6M3DF
Transliteration 03H9K14N6M3DF
By chemical elements 03Cr9Co14Н6Mo3CuV

Description

03Х9К14Н6М3Д steel is used: for the manufacture of highly loaded parts operating at temperatures from +400 °C to -196 °C in a slightly aggressive media; the various parts of the cryogenic equipment; valves of valve nodes oxygen.

Note

High-strength corrosion-resistant Maraging steel alloy with cobalt.

Standards

Name Code Standards
Sheets and strips В33 TU 14-1-2071-77
Bars and shapes В32 TU 14-1-3049-80, TU 14-1-1785-76

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Mo Co
TU 14-1-1785-76 ≤0.03 ≤0.01 ≤0.01 0.2-0.6 8.5-9.5 ≤0.1 6-7 Rest 1-1.5 0.05-0.25 3-4 13-14
Fe is the basis.
According to TU 14-1-3049-80, TU 14-1-1785-76 the chemical composition is given for steel grades 03Kh9K14N6M3D-VD and 03Kh9K14N6M3D-Sh.
When steel 03X9K14N6M3D is added to the steel as additional alloying element up to 1.5% vanadium (V), the steel has the marking 03Х9К14Н6М3ДФ.

Mechanical properties

sT|s0,2, MPa σU, MPa d5, % y, % KCU, kJ/m2 HRC
Bars hot rolled and forged in the delivery condition on the other 14-1-1785-76 (longitudinal samples)
≥1175 ≥1270 ≥10 ≥55 ≥294 ≥40
≥980 ≥1080 ≥10 ≥55 ≥490 -

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
HRC Rockwell hardness (indenter diamond spheroconical)

Technological properties

Name The value
Weldability Welded by manual and automatic organomegaly welding. Welded connections are not prone to hot and cold cracks.
Microstructure The content of residual austenite in the microstructure of 20-25%.
Corrosion resistance Steel has a high erosion resistance.