U12 (U12A)

Steel is not used for welded structures, not inclined. to temper embrittlement. Flocking sensitivity: not sensitive Temperature of critical points Ac1 = 730, Ac3 (Acm) = 820, Ar1 = 700, Mn = 200. Substitutes U10, U11 .

cutting tools, working in conditions that do not cause heating of the cutting edge: Hand taps, Taps machine small-sized, die for Krupp scanning small-sized, Needle, measuring tools of simple shape: smooth gauges, staples.

Classification

Country Section Category
CIS, Russia, Ukraine Tool steel Carbon Tool Steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % P, % C, % S, %
GOST 1435-99 97.292–98.56 0.17–0.33 0.17–0.33 < 0.2 < 0.25 < 0.25 < 0.03 1.1–1.29 < 0.028

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 209 7830
100 205 10.5 45 7809 0.469 0.252
200 200 11.8 43 7781 0.503 0.333
300 193 12.6 40 7749 0.519 0.43
400 185 13.4 37 7713 0.536 0.54
500 178 13.1 35 7675 0.553 0.665
600 166 14.8 32 7634 0.72 0.802
700 15.3 28 7592 0.611 0.964
800 15 24 7565 0.712 1.152
900 16.3 25 7489 0.703 1.196
1000 16.8 0.699

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
Tape 0.08–3 annealing 750 10
Metal rolling 590–690 325 28 50 270 Annealing

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 1435-99 annealing 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 Ar1, K Mn, K
730 820 700 200

Analogues

Germany USA Japan France United Kingdom European Union Italy China Bulgaria Hungary Poland Czech Republic Austria
1.1654 W1-11-1/2 SK2 C120E3U BW1C CT120 C120KU T11 U12 S122 N12 19221 K990

Standards

Standard Description
GOST 1435-99

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)
$$\varkappa$$ $$\frac{W}{m\cdot K}$$ 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
Ar1 K
Mn K