40KNM iron-based alloy doped with cobalt and nickel

  • Chemical composition
Fe Iron Rest
Co Cobalt 24.5 — 26.0
Si Silicon <0.3
Mn Manganese 0.3 — 0.6
Mo Molybdenum 3.8 — 4.2
Ni Nickel 39.3 — 40.7
S Sulfur <0.02
C Carbon <0.03
P Phosphorus <0.02
Domestic analogues

EP656

40NKMP (included in 2 standards)

For cores of constant inductance coils, filter chokes, broadband transformers; The alloy has anisotropy of magnetic properties, low residual magnetic induction and constant magnetic permeability in a wide range of fields. Technical requirements — according to GOST 10160−75 Precision magnetically soft alloys. Technical conditions GOST 10994−74 Precision alloys. Stamps.

Classification

Country Section Category
CIS, Russia, Ukraine Precision alloys Soft Magnetic Precision Alloys

Chemical composition

Standard Fe, % Si, % Mn, % Co, % Ni, % P, % C, % S, % Mo, %
GOST 10994-74 28.13–32.1 < 0.3 0.3–0.6 24.5–26 39.3–40.7 < 0.02 < 0.03 < 0.02 3.8–4.2

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 180 8550 0.55
100 11

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % Treatment
Tape 540 145 50
Tape cold-work 980 980 4

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Tape 110

Standards

Standard Description
GOST 10994-74

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Co % Cobalt
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)
$$\rho$$ $$\frac{kg}{m^3}$$ The density of the material
$$R\cdot 10^{-6}$$ $$\Omega\cdot m$$ 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)