25H1MF (EI10)

Bolts, leaf springs, bolts and other fasteners, operating at temperatures up to 500−510 degrees.

Classification

Country Section Category
CIS, Russia, Ukraine Heat resistant steels and alloys Heat-resistant relaxation-resistant steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % V, % P, % C, % S, % Mo, %
GOST 20072-74 95.635–97.31 0.17–0.37 0.4–0.7 1.5–1.8 < 0.2 < 0.3 0.15–0.3 < 0.03 0.22–0.29 < 0.025 0.25–0.35

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 217 7840
100 211 11.3 39.8 0.462 0.312
200 206 11.7 37.9 7790 0.396
300 198 12.8 36.9 0.475
400 191 13.9 35.9 7720 0.574
500 180 14.2 34.8 0.68
600 167 14.4 7650 0.826

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
Bars, strips GOST 20072-74 < 25 880 735 14 50 590 Tempering 880-900 ° C, oil, Holidays 640-660 ° C, air cooling
Bars, strips GOST 20072-74 780 665 16 50 590 Tempering 930-950 ° C, oil, Holidays 620-660 ° C

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy Hardening, average vacation 241–321
Alloy GOST 20072-74 annealing, hot rolling 229

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Difficult to weld sensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K
760 840 760–780 680–690

Analogues

Germany USA
1.7733 A193B14

Standards

Standard Description
GOST 20072-74

Description of chemical elements

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

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