U8

Steel is not used for welded structures, not inclined. to temper embrittlement. Flock sensitivity: not sensitive. The temperature of the critical points of the alloy: Ac1 = 720, Ar1 = 700, Mn = 245. Hardness after annealing (GOST 1435−99): HB 10 -1 = 187 MPa / Substitute U7, U10.

tool, working in conditions that do not cause heating of the cutting edge: cutters, countersinks, axes, chisels, chisels, saws longitudinal and circular, rolling rolls, center punches, screwdriver, combined pliers, side cutters.

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 97.742–98.91 0.17–0.33 0.17–0.33 < 0.2 < 0.25 < 0.25 < 0.03 0.75–0.84 < 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 7839
100 205 11.4 49 7817 0.477 0.23
200 199 12.2 46 7786 0.511 0.305
300 192 13 42 7752 0.528 0.395
400 185 13.7 38 7714 0.548 0.491
500 175 14.3 35 7676 0.565 0.625
600 166 14.8 33 7638 0.594 0.769
700 15.2 30 7600 0.624 0.931
800 14.5 24 7852 0.724 1.129
900 1.165

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers \sigma _{U}, MPa \sigma_{P}, MPa \epsilon_L, % \psi, % Treatment
Workpiece 6 1420 1230 10 37 Tempering 780 ° C, oil, leave 400 ° C
Tape 1.5 annealing 750 10

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 1435-99 annealing 1870

Technological Properties

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

Critical point temperatures

Ac1, K Ar1, K Mn, K
720 700 245

Analogues

USA Germany Japan France United Kingdom European Union Italy China Poland Czech Republic Austria
W1-7 1.1625 (C80W2) SK5 C90E2U BW1A CT80 C80KU T8 N8 19152 K980

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

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
Ar1 K
Mn K