Steel 08Х18Н5Г12АБ (NN-3B)
Designation
| Name |
The value |
| Designation GOST Cyrillic |
08Х18Н5Г12АБ |
| Designation GOST Latin |
08X18H5G12AB |
| Transliteration |
08H18N5G12AB |
| The chemical elements |
08Cr18Н5Mn12NNb |
| Name |
The value |
| Designation GOST Cyrillic |
НН-3Б |
| Designation GOST Latin |
HH-3B |
| Transliteration |
NN-3B |
| The chemical elements |
НН-3Nb |
Description
08Х18Н5Г12АБ steel is used: for the production of rolled products, forgings and stampings used in the manufacture of parts in shipbuilding and ship repairs; hull structures of ships, vessels and goods marine equipment (propeller shaft low-speed gear, axles, spindles, slides, shafts, couplings, rods, cylinders, brackets).
Note
Corrosion resistant, low steel high-strength austenitic.
When cold deformation is not more than 75%, the magnetic permeability μ ≤ 1,01 GS/C. Heat treatment on the magnetic permeability is not affected.
Standards
| Name |
Code |
Standards |
| Metal forming. Forgings |
В03 |
OST 5Р.9125-84 |
| Castings from non-ferrous metals and alloys |
В84 |
RD 9257-76 |
| Sectional and shaped rolling |
В32 |
TU 14-1-784-73 |
| Bulls. Blanks. Slabs |
В31 |
TU 14-1-853-74 |
| Castings with special properties (cast iron and steel) |
В83 |
TU 5.961-11131-79 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
N |
V |
Mo |
W |
Co |
| TU 5.961-11131-79 |
≤0.08 |
≤0.03 |
≤0.045 |
11.5-13.5 |
18-19.5 |
≤0.8 |
4.5-5.5 |
The rest |
- |
0.45-0.52 |
0.2-0.35 |
- |
- |
- |
| TU 14-1-784-73 |
≤0.08 |
≤0.03 |
≤0.045 |
11.5-13.5 |
18-19.5 |
≤0.8 |
4.5-5.5 |
The rest |
≤0.3 |
0.45-0.52 |
0.2-0.35 |
≤0.3 |
≤0.3 |
≤0.3 |
Fe is the basis.
According to RD 9257-76, TU 14-1-853-74 and TU 5.961-11131-79 the total content of Nb + Ta = 0.80-1.10%.
According to TU 14-1-853-74, deviations from the content of elements according to the chemical composition of steel are possible: 08Х18Н5Г12АБ (НН-3Б): carbon +0.010%, manganese + 0.50%, nickel + 0.50%, chromium + 0.50%, vanadium +0.10%, niobium +0.10%, nitrogen +0.030%, phosphorus +0.0050%, silicon + 0.20%. The residual content of elements in the chemical composition of the steel should not exceed: copper, cobalt, tungsten and molybdenum 0.30% of each element.
According to TU 14-1-784-73, the chemical composition is given for steel grade 08H18N5G12AB (NN-3B). The total content of Niobium (Nb) + Tantalum (Ta) should be in the range of 0.80-1.10%. Deviations in chemical composition are allowed: for carbon +0.010%, for manganese + 0.50%, for nickel + 0.50%, for chromium + 0.50%, for niobium +0.10%, for silicon +0.20 %, in nitrogen +0,030%, in phosphorus +0,0050%, in vanadium +0,10%. The residual content of elements in the chemical composition of the steel should not exceed: copper, cobalt, tungsten and molybdenum 0.30 each.
Mechanical characteristics
| Section, mm |
sT|s0,2, MPa |
σB, MPa |
d5, % |
kJ/m2, кДж/м2 |
Brinell hardness number, MPa |
| Hot rods and forgings of round and square. Quenching in water or air from 950-980 °C |
| ≤180 |
≥441 |
≥687 |
≥25 |
≥588 |
- |
| Forgings for parts resistant to the ICC. Quenching in oil or air from 950-1050 °C |
| 300 |
≥441 |
≥687 |
≥25 |
≥590 |
187-240 |
| Bars hot rolled and forged, round and square. Quenching in water from 900-1050 °C |
| ≤180 |
≥490 |
≥736 |
≥25 |
≥588 |
- |
Description mechanical marks
| Name |
Description |
| Section |
Section |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σB |
Limit short-term strength |
| d5 |
Elongation after rupture |
| kJ/m2 |
Toughness |
Physical characteristics
| Temperature |
r, кг/м3 |
l, Вт/(м · °С) |
a, 10-6 1/°С |
| 20 |
7800 |
1675 |
- |
| 100 |
- |
- |
1670 |
| 1000 |
- |
- |
2100 |
A description of the physical symbols
| Name |
Description |
| Е |
The normal elasticity modulus |
| r |
Density |
| l |
Coefficient of thermal conductivity |
| R |
UD. the resistivity |
Technological properties
| Name |
The value |
| Weldability |
Welding is not performed. |
| Workability by cutting |
Machinability similar to steel grades 12Х18Н12Т and 08KH18N12T. |
| Macrostructure and contamination |
Macrostructure of steel bars on the other 14-1-784-73 should not have shrinkage, bubbles, cracks, inclusions, visible without using the magnifying devices. |
