81NMA

For cores of magnetic heads, small transformers, chokes, relays, flaw detectors, magnetic shields, ferroprobes for use in electronic equipment of high sensitivity.

Classification

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

Chemical composition

Standard Fe, % Si, % Mn, % Ti, % Ni, % P, % C, % S, % Mo, %
GOST 10994-74 9.32–12.3 < 0.1 < 0.35 2.5–3.3 80.5–81.7 < 0.01 < 0.01 < 0.01 4.7–5.2

Information on suppliers

Physical characteristics

Temperature, °C $$E\cdot 10^{9}$$, $$MPa$$ $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ $$\rho$$, $$\frac{kg}{m^3}$$ $$R\cdot 10^{-6}$$, $$\Omega\cdot m$$
20 210 8700 0.8
100 11.8

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers $$\sigma _{U}$$, $$MPa$$ $$\sigma_{P}$$, $$MPa$$ $$\epsilon_L$$, % Treatment
Tape 640 245 50
Tape cold-work 1270 1225 2

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Tape 160
Tape cold-work 260

Standards

Standard Description
GOST 10994-74

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Ti % Titan
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)