Can steel be heat treated or otherwise changed from magnetically hard to magnetically soft?I want to use steel wool bits to visualize magnetic fields. The iron filings that you can buy for the purpose are junk - very irregular in shape and size. I have not found any source for high quality filings. I want long, thin particles, where long may be 1-2 mm and thin is 20% or so of the length. High aspect ratio is another way to put it. Particle length can certainly have a good degree of variability; I‘m more interested in the high aspect ratio.If you imagine small bits of 0000 steel wool, that‘s what I‘m looking for. But steel will retain a field once it has been exposed to a magnet. I want the particles to be magnetically soft so they don‘t retain the field. Is there any way to treat bits of steel wool to make it magnetically soft, or is there a source for high aspect ratio iron (not steel) bits?
They are unlimited you just have to move to diffrent areas on map
I think you have hard and soft backwards. Hard magnetic materials have a squareish BH curve and retain a fairly large residual field after they are magnetized. Soft material does not have much hysteresis or a residual field. Most common steel has a relatively low permeability and thus doesn't respond much to external fields. They are magnetically soft. In general, iron is hard. I don't think your steel wool is really steel.
