High-temp iron infused filament?  

RE: High-temp iron infused filament?

A thought, make a mould and use a high temp epoxy and metal powder.

From my magnetics experiments, you may find that ferromagnetic filament doesn't work as you would expect.

RE: High-temp iron infused filament?

I find this a little funny, cause I spent all of today testing different iron powder densities in resin casts... 🤣 

It sounds like you have some experience with this though. If you don't mind me asking, what resin did you use? And what iron to resin ratio? 

RE: High-temp iron infused filament?

Rather than epoxy, you might try packing the powder into the mold and wetting it with low-viscosity CA glue as a binder. You should be able to get a much higher iron content than any printable filament, or even pourable resin mix, could contain.

RE: High-temp iron infused filament?

I have experience trying to do some magnetics stuff at work and it was problematic.  Magnetic projects are dependent on many things and we found that theory was much nicer than the real world.  For some of our stuff, we used a low viscosity epoxy in different situations.  Cannot go into details due to IP issue.

RE: High-temp iron infused filament?

This may or may not work.  CA may not handle the temperature and may break down.  I do know that some epoxies will get soft at higher temps and I used to remove cured epoxy from containers using  heat gun.

RE: High-temp iron infused filament?

On this topic, you can thin epoxy with acetone or denatured alcohol.  I just did this with JB weld last week for the first time.  It worked really well for my usage. 

Another note, epoxy is exothermic so it gets hot when mixed in large quantities.  I have had epoxy melt through plastic containers and today, I was making a small epoxy cast and it got hot so I took my thermal camera and it was at 54°.  It was only 15ml.  Warm epoxy cures faster. 

My first experience with this issue was when the epoxy cured while I was pouring it and the epoxy cured in about 15 seconds.  Made a nice little piece of artwork.  🙂

RE: High-temp iron infused filament?

I have a technical question.  Is there a reason you want to use iron filled?  Is is for magnetic purposes? 

For moving magnetic fields, aluminium will also be affected as well as copper.  I found this out the hard way when things didn't work as expected with copper and aluminium plates.  To prove my theory, I took a strong magnet and put it on an aluminium plate and turned it 90 degrees expecting the magnet to fall to the bench, it slowly slid down the plate.  As aluminium moves in a magnetic field, eddy currents are produced and these are the reason that the magnet sticks.  Same with copper.

There is also the option of contracting out the 3D printing to a place that will print with metal.  It may not be that expensive, depending on the project.

RE: High-temp iron infused filament?

Yes I need it for magnetic purposes. I need it to be high resistance and high permeability for the stator to work well. It needs to be very close to the permeability of iron.

I just finished experimenting with thinning epoxy with alcohol before reading your post. I could swear you have a camera on me or something... 🤣 

RE: High-temp iron infused filament?

Posted by: @robin_13

This may or may not work.  CA may not handle the temperature and may break down.  I do know that some epoxies will get soft at higher temps and I used to remove cured epoxy from containers using  heat gun.

Well, it's to be used in an application where a printable thermoplastic is being considered. It'll at least be better than PLA.

RE: High-temp iron infused filament?

I actually just tried the CA glue. It's super low viscosity so that's appealing, the only issue I found is that if you try to mix it with a powder it hardens instantly. No time to even mix it in properly (it even started smoking because it was curing so fast) I didn't try adding it to the powder after it was in the mould because I figured then only the outside layer would be hardened and everything else would still be powder.

RE: High-temp iron infused filament?

That's interesting. I wonder if there's some inhibitor that could be used to slow it...maybe you could chill it to slow the initial reaction? Might also be caused by moisture in the powder that could be baked out.

RE: High-temp iron infused filament?

Look up BASF Ultrafuse and Virtual Foundry - for high metal content filaments that are post processed and sintered in a kiln to leave pure metal parts, you can do this at home (if you have a suitable kiln) if you don't want to send the files to a metal printing service.

Cheerio,

RE: High-temp iron infused filament?

As far as I'm aware, Ultrafuse is only available in stainless steel. Virtual Foundry has a "high carbon iron" filament that's probably okay for magnetics, but it's expensive, and weirdly, they claim not to have tested sintering it. I suspect that actually means it doesn't sinter well.

RE: High-temp iron infused filament?

Yeah I looked up that BASF material, and it only comes in stainless, but they claim it is still magnetic. Also the sintering process is very complicated. It looks like you send it in and they do it for you. I'll have to get some and see how it does.

I'm also curious if there is a way to slow down the CA curing. I had thought about chilling it but discounted it until I hear someone else say the same thing. I'll see if I can give it a try this week

RE: High-temp iron infused filament?

This is an interesting discussion since I went through much of it at work in R&D projects.

I looked at metal printed items and we even talked about purchasing a method of metal printing, All methods were not low cost but would still save us money since some of the parts I was getting machined were over $5000 each.  This was before metalized filaments became available.  I know that if I use metalized filaments, there is a place I can send them for the sintering process.  Now the sintering process is not an easy task and you do need a sintering oven.  The oven needs to be able to get hot enough to melt the metal you are using.  We had an oven at work that would do this but we couldn't control the process over the length of time.  Looks like things have gotten better over the years since I looked at it.

With what is needed, I feel you need to do some tests with powders and find out if the magnetic properties will meet your requirements.  We had to order special steel for our work, to provide the magnetic fields we needed.  Tried electromagnets and finally ended up using neodymium magnets.

You may find that the metal powders may not give you the field strengths you need and that has to be tested due to density and the micro-gaps between the individual powder grain.  Also look at the shape of the powders to see if they are more flake or round as this could affect what you are trying to do.  It may be easier and cheaper to just machine the stater. 

You may have to contract out the 3D printing part of the project.  If you need density, laser sintering may be the only process that will work.

Some reading.  Getting Started with Filamet™: Tips for Debinding and Sintering Metal Filament

Also, to slow down CA curing time, cold materials and glue.  And use layers.  Bit of powder, bit of glue.  Bit of powder, bit of glue.  This is a technique for using baking powder and CA for metal repair.  Mix super glue and baking soda for the best fix-all hack ever  which is very interesting.  You can pack the powder and then add the adhesive.

RE: High-temp iron infused filament?

You might also look at alternative approaches like laminated cores. Maybe you can get something done in some type of electrical steel from a laser cutting service...

RE: High-temp iron infused filament?

Very helpful stuff. I've been looking into magnetic properties of iron powder, but most the resources I can find are mainly for like magnetic field visualization, not for actually using the powder as a magnetic material. You mentioned that you got some special powder for your needs? If you can I'd love some tips there (no worries if you can't), I'm not sure which powder to get for the best results 

As for the laminated core, I've actually looked into that, but I can't find a seller that sells silicon steel for less that like a 1 ton quantity... If I could get some in small quantities I'd love to do some R&D with it

RE: High-temp iron infused filament?

Thanks for sharing these insights mate as I found it very much useful and informative.

RE: High-temp iron infused filament?

Another option for adhesive is polyurethane glue.  It can be thinned as well.  Longer curing time, harder and may handle the heat better.