Steel 03KH21N21M4GB (ЗИ35)

Designation

Name The value
Designation GOST Cyrillic 03Х21Н21М4ГБ
Designation GOST Latin 03X21H21M4GB
Transliteration 03H21N21M4GB
By chemical elements 03Cr21Н21Mo4MnNb
Name The value
Designation GOST Cyrillic ЗИ35
Designation GOST Latin ZI35
Transliteration ZI35
By chemical elements ЗИ35

Description

03KH21N21M4GB steel is used: for the manufacture of welded structures and components operating in conditions of hot phosphoric acid with a mixture of fluorine and sulfur compounds, and sulfuric acid of low concentration at temperatures up to +80 °C, nitric acid at temperatures up to +95 °C; parts of equipment for chemical industry (production of phosphoric acid, fertilizers, cellulose acetate, vinyl acetate, etc.); equipment, working in conditions of intensive wear (mixers, separators, extractors); welding electrodes used in the manufacture of equipment for energy and chemical engineering.

Note

Steel is a complex alloy corrosion-resistant austenitic class.

Standards

Name Code Standards
Processing of metals by pressure. Forgings В03 GOST 25054-81
Sheets and strips В33 GOST 5582-75, GOST 7350-77, TU 14-1-4364-87
Classification, nomenclature and General rules В30 GOST 5632-72
Blanks. Of the workpiece. Slabs В31 OST 3-1686-90, TU 14-1-2134-77
Thermal and thermochemical treatment of metals В04 STP 26.260.484-2004
Bars and shapes В32 TU 14-1-1190-75, TU 14-11-245-88, TU 14-1-4319-87
Steel pipes and fittings to them В62 TU 14-3-694-78, TU 14-3-696-78, TU 14-3-751-78

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Ti Mo W
GOST 5632-72 0.03 ≤0.02 ≤0.03 1.8-2.5 20-22 ≤0.6 20-22 Rest ≤0.3 ≤0.2 ≤0.2 3.4-3.7 ≤0.2
Fe is the basis.
According to GOST 5632-72 the content of Nb% = 15C% is 0.8%.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % d10 y, %
Hot rolled sheet (of 1.5-3.9 mm) and cold rolled (0,7-3,9 mm) steel according to GOST 5582-75. Quenching in water or air with 1080-1130 °C
- ≥245 ≥540 - ≥25 -
Hot rolled sheet (4,0-25,0 mm) and cold rolled (4,0-5,0 mm) steel according to GOST 7350-77. Quenching in water or under a water shower with 1060-1120 °C
- ≥295 ≥590 ≥30 - -
Bars hot rolled and forged at STP 26.260.484-2004. Quenching in water or under a water shower with 1060-1120 °C
≥300 ≥600 ≥30 - ≥30

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
d10 Elongation after rupture
y The relative narrowing

Technological properties

Name The value
Weldability Without ogranicheniy
Features of heat treatment Steel products 03KH21N21M4GB should be hardened with 1060-1120 °C, holding time wall thickness up to 15mm - 30 min, more than 15 mm - 30 min + 1 min per 1 mm of maximum wall thickness; the product is cooled in water or air.