12MH

For superheater pipes, pipelines and rigs high pressure collector; forgings for steam boilers and steam lines; gas turbine engine components; as the base layer in the manufacture of hot-rolled sheet of two-layer corrosion.

Classification

Country Section Category
CIS, Russia, Ukraine Heat resistant steels and alloys Heat resistant low alloy steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Ti, % Cu, % Ni, % V, % P, % C, % S, % Mo, % W, %
GOST 20072-74 96.635–98.54 0.17–0.37 0.4–0.7 0.4–0.7 < 0.03 < 0.2 < 0.3 < 0.05 < 0.03 0.09–0.16 < 0.025 0.4–0.6 < 0.2

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 212 7850
100 206 11.2 50 7830 0.473 0.24
200 200 12.5 50 7800 0.519 0.33
300 195 12.7 50 7760 0.565 0.41
400 189 12.9 49 7730 0.594 0.54
500 179 13.2 47 7690 0.653 0.64
600 170 13.5 46 7650 0.733 0.74
700 160 13.8 44 7610 0.888 0.9

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % $$\psi$$, % $$KCU\cdot 10^{3}$$, $$\frac{J}{m^2}$$ Treatment
Pipes are hot deformed. GOST 550-75 412 245 21 45 690
Rod GOST 20072-74 90 410 235 21 45 590 Normalization of 910-930 ° C, air Accommodation 670-690 ° C

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy Hardening, average vacation 1820
Alloy GOST 20072-74 annealing, hot rolling 217
Pipes are hot deformed. GOST 550-75 1560

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
no limits sensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K
723 885 803 715

Analogues

USA Germany
11562 1.7335 (13CrMo4-5)

Standards

Standard Description
GOST 20072-74

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Cr % Chrome
Ti % Titan
Cu % Copper
Ni % Nickel
V % Vanadium
P % Phosphorus
C % Carbon
S % Sulfur
Mo % Molybdenum
W % Tungsten

Description of physical characteristics

Parameter Units of measurement Description
$$E\cdot 10^{9}$$ $$MPa$$ Elastic modulus
$$\alpha\cdot 10^{6}$$ $$K^{-1}$$ Coefficient of thermal (linear) expansion (range 20°C–T)
$$\varkappa$$ $$\frac{W}{m\cdot K}$$ Coefficient of thermal conductivity (the heat capacity of the material)
$$\rho$$ $$\frac{kg}{m^3}$$ The density of the material
$$c\cdot 10^{-3}$$ $$\frac{J}{kg\cdot K}$$ The specific heat of the material (range 20°C–T)
$$R\cdot 10^{-6}$$ $$\Omega\cdot m$$ Electrical resistivity

Description of mechanical properties

Parameter Units of measurement Description
$$\sigma _{U}$$ $$MPa$$ Ultimate tensile strength
$$\sigma_{P}$$ $$MPa$$ Proportionality limit
$$\epsilon_L$$ % Elongation at break (longitudinal)
$$\psi$$ % Reduction in cross section on fracture
$$KCU\cdot 10^{3}$$ $$\frac{J}{m^2}$$ Impact toughness

Designation of types of weldability

Parameter Units of measurement Description
no limits Welding is performed without heating and without subsequent heat treatment
Boundedly welded Welding is possible with heating up to 100–120 °C and subsequent heat treatment
Difficult to weld For obtaining quality welded joints, additional operations are required: heating up to 200–300 °C for welding, heat treatment after welding — annealing
Not applicable for welded structures

Description of temperatures of critical points

Parameter Units of measurement Description
Ac1 K
Ac3(Acm) K
Ar3(Arcm) K
Ar1 K