40H9S2 (4Х9С2)

Valves of automobile, tractor and diesel engines, heat exchangers, grate.

intake and exhaust engine valves, tube heat exchangers, heat exchangers, grate, fasteners; heat-resistant steel, martensitic class

Classification

Country Section Category
CIS, Russia, Ukraine Heat resistant steels and alloys Heat resistant high alloy steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Ti, % Cu, % Ni, % P, % C, % S, %
GOST 5632-72 84.595–89.65 2–3 < 0.8 8–10 < 0.2 < 0.3 < 0.6 < 0.03 0.35–0.45 < 0.025

Information on suppliers

Physical characteristics

Temperature, °C $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\varkappa$$, $$\frac{W}{m\cdot K}$$ $$\rho$$, $$\frac{kg}{m^3}$$
20 7630
100 11.1 17 7610
200 12.7 7580
300 20
400 14.3 7510

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % $$\psi$$, % Treatment
Rod GOST 5949-75 740 440 15 35 Annealing 850-870 ° C, air

Technological Properties

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

Critical point temperatures

Ac1, K Ac3(Acm), K Ar3(Arcm), K Ar1, K
900 970 970 810

Analogues

Germany USA
G-X45CrSi9-3 S65007

Standards

Standard Description
GOST 5632-72
GOST 5949-75

Description of chemical elements

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

Description of physical characteristics

Parameter Units of measurement Description
$$\alpha\cdot 10^{6}$$ $$K^{-1}$$ 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

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
Ac3(Acm) K
Ar3(Arcm) K
Ar1 K