40HFA (40HF)

The improved state-spline shafts, rods, set screws, crosshead, excavating shafts and other parts operating at temperatures up to 400 ° C; after quenching and low tempering — worm shafts and other components increased durability.

Classification

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

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % V, % P, % C, % S, %
GOST 4543-71 96.46–98.06 0.17–0.37 0.5–0.8 0.8–1.1 < 0.3 < 0.3 0.1–0.18 < 0.025 0.37–0.44 < 0.025

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}
20 215 37 7810
100 212 12.1 37 0.466
200 205 12.6 37 0.508
300 199 13 36 0.529
400 182 13.3 33 0.563
500 173 13.8 31 0.592
600 166 14.2 31 0.621
700 144 14.6 30 0.634
800 135 11.8 28 0.664

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 25 880 735 10 50 880 Hardening and tempering
Forgings 100–300 615 395 15 40 540 Hardening and tempering
Forgings 300–500 615 395 13 35 490 Hardening and tempering

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 4543-71 annealing 241

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
760 800 725 680 218

Analogues

USA Germany
G41400 1.7223 (41CrMo4)

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
V % Vanadium
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)

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