The invention discloses ultrathin iron-
silicon-aluminum flaky
powder and a preparation method thereof, and particularly relates to the field of
metal and
alloy powder preparation. The method comprises the steps that firstly, an
alloy material containing iron,
silicon and aluminum is melted into
alloy steel liquid through medium-frequency induction or
electric arc induction, the steel liquid flows out through a flow limiting opening with the
diameter being 3-8 mm, and gas atomization is conducted on the steel liquid through high-pressure
nitrogen /
argon; spraying atomized
molten steel drops to the surface of a
copper roller or a
copper disc rotating at a high speed, and carrying out
quenching solidification to form flaky
powder; finally, the flaky powder is subjected to annealing treatment under the protection of
nitrogen /
argon; and grading and screening according to the
granularity requirement to finally obtain the ultrathin iron-
silicon-aluminum sheet-shaped powder. According to the preparation method, the thickness of the flaky powder can be further reduced, and the flake
diameter of the flaky powder is increased, so that the length-
diameter ratio is increased, and the high-frequency magnetic
conductivity is further improved.