77NMD (EP233, 77NMDP)

For cores of small transformers, chokes and relays, operating in weak fields, magnetic shields. In small thicknesses (0.05 to 0.02 mm) — for cores of pulse transformers, magnetic amplifiers and solid-state relays

Classification

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

Chemical composition

Standard Fe, % Si, % Mn, % Cu, % Ni, % P, % C, % S, % Mo, %
GOST 10994-74 9.74–15.7 0.1–0.3 < 1.4 4.8–6 75.5–78 < 0.02 < 0.03 < 0.01 3.9–4.5

Information on suppliers

Physical characteristics

Temperature, °C \alpha\cdot 10^{6}, K^{-1} \rho, \frac{kg}{m^3} R\cdot 10^{-6}, \Omega\cdot m
20 8600 0.55
100 12.7

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers \sigma _{U}, MPa \sigma_{P}, MPa \epsilon_L, % Treatment
Tape 540 145 40
Tape cold-work 980 980 2

Brinell hardness number

Rolling Standard Classifiers Value, HBW
Tape 110
Tape cold-work 230

Standards

Standard Description
GOST 10994-74

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Cu % Copper
Ni % Nickel
P % Phosphorus
C % Carbon
S % Sulfur
Mo % Molybdenum

Description of physical characteristics

Parameter Units of measurement Description
\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)