40HN2MA (40HNMA)

Shafts, valves, connecting rod caps and other heavy duty parts. Rolls for cold rolling.

Crankshafts, valves, connecting rods, covers of rods responsible bolts, gears, cam clutches, drives, and other heavy duty parts. Rolls for cold rolling of metals. Steel 40HN2MA-W manufactured pipes for cold-tail helicopter shafts

Classification

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

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % P, % C, % S, % Mo, %
GOST 4543-71 95.24–96.96 0.17–0.37 0.5–0.8 0.6–0.9 < 0.3 1.25–1.65 < 0.025 0.37–0.44 < 0.025 0.15–0.25

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$c\cdot 10^{-3}$$, $$\frac{J}{kg\cdot K}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 215 39 7850 0.331
100 211 11.6 38 0.49
200 201 12.1 37 0.506
300 190 12.7 37 0.522
400 177 13.2 35 0.536
500 173 13.6 33 0.565
600 13.9 31
700 29
800 27

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 930 12 50 780 Hardening and tempering

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Alloy GOST 4543-71 annealing 269

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Difficult to weld sensitive not inclined

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K Mn, K
730 820 550 380 320

Analogues

USA Germany
Gr.9840 1.6582 (34CrNiMo6)

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
Mo % Molybdenum

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
Ar3(Arcm) K
Ar1 K
Mn K