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

s_T\|s_0,2, MPa	σ_U, 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
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
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.

Steel 03Х9К14Н6М3Д (ЭП921; 03Х9К14Н6М3ДФ)

Designation

Description