Steel 12H25N16G7AR (ЭИ835)

Designation

Name The value
Designation GOST Cyrillic 12Х25Н16Г7АР
Designation GOST Latin 12X25H16G7AP
Transliteration 12H25N16G7AR
By chemical elements 12Cr25Н16Mn7NB
Name The value
Designation GOST Cyrillic ЭИ835
Designation GOST Latin EI835
Transliteration EhI835
By chemical elements -

Description

12H25N16G7AR steel is used: for the production of sheets, wires, tubes, tapes, parts operating up to +950 °C at moderate loads; details of the turbine (parts of gas pipeline systems, combustion chambers, diaphragms, sheet metal parts), operating at temperatures up to +1050 °C and pressures up to 7760 kg/m3; the welding wire used for welding parts and welding of steel structures in energy engineering; welding electrodes; solid-rolled rings for different purposes.

Note

Heat-resistant steel and heat resistant austenitic class.
The recommended maximum operating temperature for a long time +1050 °C.
Temperature intense scaling in air +1100 °C.
Steel 12H25N16G7AR, it is recommended to replace heat-resistant Nickel-based alloys: KHN75MBTJU (ЭИ602), KHN78T (ЭИ435).

Standards

Name Code Standards
Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Sheets and strips В23 GOST 19904-90, GOST 103-2006
Sheets and strips В33 GOST 4405-75, GOST 5582-75, GOST 7350-77, TU 14-1-1747-76
Tape В34 GOST 4986-79, TU 14-1-1007-74
Classification, nomenclature and General rules В30 GOST 5632-72
Bars and shapes В32 GOST 5949-75, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, OST 1 92049-76, TU 14-1-225-72, TU 14-1-3564-83, TU 14-11-245-88
Blanks. Of the workpiece. Slabs В21 OST 1 90176-75
Blanks. Of the workpiece. Slabs В31 OST 3-1686-90, OST 1 90160-74, OST 1 90387-89, TU 14-1-1214-75
Thermal and thermochemical treatment of metals В04 ST ЦКБА 016-2005
Processing of metals by pressure. Forgings В03 TU 14-1-1530-75, TU 14-1-2902-80
Welding and cutting metals. Soldering, riveting В05 TU 14-1-997-74, TU 14-1-997-2012

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu N V B Ti Mo W
TU 14-1-1747-76 ≤0.12 ≤0.02 ≤0.035 5-7 23-26 ≤1 15-18 Rest ≤0.2 0.3-0.45 - ≤0.01 - - -
GOST 5632-72 ≤0.12 ≤0.02 ≤0.035 5-7 23-26 ≤1 15-18 Rest ≤0.3 0.3-0.45 ≤0.2 ≤0.01 ≤0.2 ≤0.3 ≤0.2
TU 14-1-225-72 ≤0.12 ≤0.02 ≤0.035 5-7 23-26 ≤1 15-18 Rest - 0.3-0.45 - ≤0.01 - - -
TU 14-1-2902-80 ≤0.12 ≤0.015 ≤0.035 5-7 23-26 ≤1 15-18 Rest ≤0.3 0.3-0.45 ≤0.2 ≤0.01 ≤0.2 ≤0.3 ≤0.2
Fe is the basis.
According to TU 14-1-2902-80 the chemical composition is given for 12Х25Н16Г7АР-Ш.
According to TU 14-1-225-72 the chemical composition is given for 12Х25Н16Г7АР and 12Х25Н16Г7АР-Ш. The 12Х25Н16Г7АР-Ш grade of the highest quality grade sets the phosphorus content P≤0,025%.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % d4 y, % KCU, kJ/m2 HB, MPa
Blank pieces of pipe fittings and welded assemblies at ST CKBA 016-2005. Quenching in water from 1050-1150 °C (delay of 2.0 min/mm the largest section)
≤180 ≥343 ≥735 ≥45 - ≥45 ≥2450 163-217
Leaves. Annealing in air or in water 1050-1100 °C
- ≥176 ≥30 - - - -
Steel cold-rolled sheet (0.8 to 3.9 mm) as supplied
- - ≤980 ≥35 - - - -
Annealing in air or in water 1050-1150 °C (aging of 0.5-1.0 h)
Образец т/о ≥345 ≥740 ≥45 - ≥45 - 160-217
Forgings, rods, rolled and forged. Annealing in air or in water 1050-1150 °C (aging of 0.5-1.0 h)
- ≥180 ≥15 - ≥20 - -
Steel cold-rolled sheet (0.8 to 3.9 mm) as supplied
- - ≥180 ≥30 - - - -
Annealing in air or in water 1050-1150 °C (aging of 0.5-1.0 h)
≥330 ≥700 ≥40 - - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 380-440 770-850 45-67 49-78 - - -
Ring forged in OST 1 92049-76. Quenching in water or air from 1050-1150 °C (aging of 0.5-1.0 h)
25 ≥345 ≥735 ≥38 - ≥38 - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 225-245 560-610 48-57 64-76 - - -
Cold-rolled steel strip of 0.05-2.00 mm according to GOST 4986-79. Quenching in water or air at 1050-1100 °C (samples)
0.2-2 - ≥690 - ≥30 - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 205-225 510-580 40-53 56-74 - - -
Cold-rolled steel strip of 0.05-2.00 mm according to GOST 4986-79. Quenching in water or air at 1050-1100 °C (samples)
0.2 - ≥690 - ≥15 - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 175-215 380-450 22-33 22-34 - - -
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 from 1050-1100 °C
- ≥180 ≥30 - - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 165-205 275-350 19-28 24-40 - - -
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 from 1050-1100 °C
- ≤980 ≥35 - - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 125-175 175-235 20-36 25-44 - - -
Hot rolled sheet (4,0-25,0 mm) and cold rolled (4,0-5,0 mm) steel according to GOST 7350-77. Annealing in air or in water 1050-1150 °C
≥390 ≥740 ≥50 - - - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- 49-98 98-135 50-64 43-60 - - -
Bars hot rolled and forged according to GOST 5949-75. Annealing in air or in water 1050-1150 °C
≥325 ≥690 ≥40 - ≥45 - -
Rod. Annealing in air from 1150 °C (exposure 40 min)
- - 39-59 50-70 41-62 - - -
Forming at OST 1 90176-75. Annealing in air from 1050-1150 °C (aging of 0.5-1.0 h)
≥343 ≥736 ≥45 - ≥45 - 163-217
Rod. Annealing in air from 1150 °C (exposure 40 min)
- - 29-39 59-64 48-69 - - -

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
d4 Elongation after rupture
y The relative narrowing
KCU Toughness
HB Brinell hardness number

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) R, Mr. · m a, 10-6 1/°C
0 193 7820 14 1000 -
20 1965 7820 1382 1060 -
100 186 - 15 1100 166
200 178 - 16 1170 162
300 171 - 18 1200 168
400 163 - 19 1240 174
500 156 - 21 1280 18
600 147 - 22 1310 183
700 138 - 24 1330 185
800 131 - 26 1360 187
900 127 - 28 1390 187
1100 - - - - 189

A description of the physical symbols

Name Description
Е The normal elasticity modulus
r Density
l Coefficient of thermal conductivity
R UD. the resistivity
a The coefficient of linear expansion

Technological properties

Name The value
Weldability Steel is welded all types of welding. Welded assemblies of steel grades 12H25N16G7AR, 12H25N16G7AR-sh should be subjected to heat treatment regime: quenching from temperatures from 950 °C to 1050 °C with air cooling. Heat treatment of welded assemblies, made of steel grades 12H25N16G7AR, 12H25N16G7AR-sh where allowed reduced compared to the base metal strength of weld and stress relief is not required, it is allowed to produce, in addition to Assembly operating at cryogenic temperatures.
The temperature of forging Beginning - 1170 °C, the end - 950 °C. air Cooling.
Features of heat treatment The workpiece of steel grade 12H25N16G7AR diameter (thickness) of less than 10 mm is allowed to cool from the quenching temperature in the air.