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parts with thin sections of hardened elements: the mean modulus gears, bushings, plates and other details; after the surface hardening with heating HDTV — details, which are subject to high wear resistance requirements in the viscous core, operating at high speeds and medium-specific pressures.

Classification

Country Section Category
CIS, Russia, Ukraine Structural steel Carbonaceous quality structural steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % As, % P, % C, % S, %
GOST 1050-88 97.965–99.35 0.1–0.3 < 0.2 < 0.15 < 0.3 < 0.3 < 0.08 < 0.035 0.55–0.63 < 0.04

Information on suppliers

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
Metal rolling GOST 1050-88 < 80 600 315 12 28 Normalization
Metal rolling 130 hot rolling 600 300 10 25 350 Normalization

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Metal rolling GOST 1050-88 hot rolling 255
Metal rolling GOST 1050-88 annealing, hot rolling 217

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Not applicable for welded structures not sensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K
720 785

Standards

Standard Description
GOST 1050-88

Description of chemical elements

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

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