50X

Shafts, spindles, set screws, large gears, gear shafts, thrust washers, rollers and other hot rolling improves the detail, which are requirements of high hardness, wear resistance, strength and operating at low impact loads.

Classification

Country Section Category
CIS, Russia, Ukraine Structural steel Alloyed structural steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % P, % C, % S, %
GOST 4543-71 96.52–98.07 0.17–0.37 0.5–0.8 0.8–1.1 < 0.3 < 0.3 < 0.035 0.46–0.54 < 0.035

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\rho$$, $$\frac{kg}{m^3}$$
20 207 7820
100 12.8
200 13
300 13.8

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
Rod GOST 4543-71 25 1080 885 9 40 390 Tempering 830 ° C, oil, leave 520 ° C, the water
Forgings < 100 590 345 18 45 590 Normalization
Forgings 100–300 590 345 17 40 540 Normalization
Forgings 300–500 590 345 14 38 490 Normalization
Forgings 500–800 590 345 12 38 390 Normalization

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 4543-71 annealing 229

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Difficult to weld sensitive inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K Mn, K
720 770 693 660 250

Analogues

USA Germany
H51500 1.7228 (50CrMo4)

Standards

Standard Description
GOST 4543-71

Description of chemical elements

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

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)
$$\rho$$ $$\frac{kg}{m^3}$$ The density of the material

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
Mn K