FINEMET® is registered trade mark of Hitachi Metals
is a Nanocrystalline amorphous soft magnetic metal.
It's phase characteristics is far better than conventional
core material such as Ni and Co-based amorphous metal.
Amorphous metals do not have a crystalline structure
like other magnetic materials. All the atoms in an amorphous
metal are randomly arranged, thus giving it a higher
resistivity (about three times) value than that for
crystalline counterparts. Amorphous alloys are prepared
by cooling the melt at a rate of about million degrees
per second. This fast cooling does not give the atoms
enough time to rearrange into a stable crystalline form.
As a result one gets metastable amorphous structure.
Because of the absence of crystalline structure amorphous
alloys are magnetically soft (lower coercivity, lower
core loss, higher permeability). High resistivity gives
lower loss at higher frequencies. The losses are among
the lowest of any known magnetic materials.
1) Satisfy both high saturation magnetic flux density
and high permeability
High saturation magnetic flux density comparable to
Fe-based amorphous metal. High permeability comparable
to Co-based amorphous metal.
Low core loss.
1/5th the core loss of Fe based amorphous metal and
approximately the same core loss as Co-based amorphous
Less affected by mechanical stress. Very low audio noise
Excellent temperature characteristics and small aging
Small permeability variation (less than ±10%)
at a temperature range of -50°C~150°C. Unlike
Co-based amorphous metals, aging effects are very small.
Excellent high frequency characteristics.
High permeability and low core loss over wide frequency
range, which is equivalent to Co-based amorphous metal.
Flexibility to control magnetic properties “B-H
curve shape” during annealing
Three types of B-H curve squareness, high, middle and
low remanence ratio, corresponding to various applications.