I stand corrected. I hadn't encountered ground down ferrite as you
describe. I should have realized it existed, though, since I've used
ferrite loaded paints and silicone rubber, which must contain ferrite in
this form. Thanks for the correction, and to the original poster I
apologize -- please disregard my posting.

Am I correct in assuming you'd end up with ferrites of lower
permeability (and higher saturation flux density) than the unpowdered
original, due the inevitable air gaps between particles?

A major manufacturer of ferrite-loaded materials such as paints and
silicone rubbers is Emerson & Cuming. They might be a possible source of
ferrite in powdered form.

Roy Lewallen, W7EL

Ed Price wrote:


"Roy Lewallen" wrote in message
...

There's no such thing as "powdered ferrite". Ferrites are ceramics,
made by firing special clays at high temperatures with proprietary
processes. The process is similar in many ways to firing pottery, and
making a ferrite rod from "powdered ferrite" would be as hopeless as
making a ceramic vase from ground-up coffe mugs.

Roy Lewallen, W7EL



After the sintering step, the resultant granules are ground down to a
reasonably uniform size. These powders (and I wouldn't know what else to
call them) can then be compressed into pellets, extruded into rods,
mixed with a vehicle and cast as thin films, or sprayed onto substrates.
You can even blend them into a binding carrier (like wax or epoxy) and
create physical shapes (like rods or blocks).

The density of the ferrite particles can be controlled, yielding
inter-particle gaps as desired.

Ferrite exists in it's granular (powdered) form. However, since there's
likely little market for this stage, you might have trouble buying a few
pounds of it.

Ed
wb6wsn