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Electronics => Projects, Designs, and Technical Stuff => Topic started by: kelesekrem on October 03, 2017, 05:49:27 pm

Title: induction heater for 3d printer(600 C)
Post by: kelesekrem on October 03, 2017, 05:49:27 pm
I want to melt aluminum with an induction heater and can I print it in 3d?
how can I design an induction heater?
Title: Re: induction heater for 3d printer(600 C)
Post by: CM800 on October 03, 2017, 06:15:48 pm
I basically wouldn't go there, you'll find huge issues with thermal expansion / contraction etc, not to mention what kind of hot-end material you'd use.

 I believe people have tried without success, hence why laser sintering and powder-plasma deposition is the only common additive manufacturing methods for metals.


EDIT: forgot to mention: Oxide Layers, Wetting / Surface Tension
Title: Re: induction heater for 3d printer(600 C)
Post by: strawberry on October 03, 2017, 10:28:58 pm
I believe people have tried without success, hence why laser sintering and powder-plasma deposition is the only common additive manufacturing methods for metals.
Some high speed railroad rails are welded pouring liquid metal in mold to join two peaces of track..
Title: Re: induction heater for 3d printer(600 C)
Post by: thm_w on October 03, 2017, 10:57:09 pm
Some high speed railroad rails are welded pouring liquid metal in mold to join two peaces of track..

You are describing welding and not additive manufacturing though.
Imagine how hot the aluminum on the print surface has to be, you'd need some kind of oven-like enclosure.
Title: Re: induction heater for 3d printer(600 C)
Post by: CM800 on October 03, 2017, 11:13:46 pm
Some high speed railroad rails are welded pouring liquid metal in mold to join two peaces of track..

You are describing welding and not additive manufacturing though.
Imagine how hot the aluminum on the print surface has to be, you'd need some kind of oven-like enclosure.

Indeed, the reason for heated chambers is to keep all the material near the liquid-solid boundary, so that you can let the entirety of it cool down together to help deal with thermal stress that would occur from multiple bonds across it all contracting at different rates.

You would need motors that operate in temperatures unseen before, Even watercooling would be an issue, you'd have to find pipes that could withstand the chamber temperature, and water would boil off possibly before it made a major effect on the motor..

Just far too many issues. I mean... I could build that system, I'm pretty sure. But it would cost A HECK of a lot more then an SLS machine, and be a lot less reliable too, plus rather inaccurate.
Title: Re: induction heater for 3d printer(600 C)
Post by: hlavac on October 05, 2017, 12:51:39 am
You cant 3D print metal the same way as plastic because it goes liquid when it melts instead of gradually softening like the plastic does
Title: Re: induction heater for 3d printer(600 C)
Post by: texaspyro on October 05, 2017, 04:08:33 am
Don't forget... aluminum fires are great fun... NOT!
Title: Re: induction heater for 3d printer(600 C)
Post by: kelesekrem on October 05, 2017, 11:01:44 am
thanks friends :)
well,I have to design an induction heater for the hard plastics. I have different circuits on the internet, I want to make a 500 w heater. Will you be a helper?
Title: Re: induction heater for 3d printer(600 C)
Post by: BenKenobi on October 05, 2017, 04:19:29 pm
Having handled coding for a major manufacturers aluminium engine production I can promise you that in a domestic environment you don't even want to go there, even in a commercial you have to be so careful with this stuff.

Aluminium loves Oxygen and does everything it can to react with it, then there's the vapour it gives off, this is nasty in its own right. Whilst aluminium doesn't 'burn' in the manner most think of fire it can and does explode, aluminimum powder is a prime ingredient in thermite - this burns with a ferocity that is spectacular. You absolutely don't want water any where near it whilst in a molten state, even moisture in the air / condensation.

Take head of Texaspyro's warning and search the consequences of playing with molten aluminium ...
Title: Re: induction heater for 3d printer(600 C)
Post by: Old Don on October 05, 2017, 04:36:06 pm
While you can't 3D print aluminium in a standard 3D printer, there are 3D filaments available that are 80-90% metal and you can make a sintered metal part by burning off the remaining plastic carriers. The part will shrink, but that can be adjusted by resizing the original size to allow the final size is what you want.

Here's one link:   https://www.amazon.com/dp/B06XXW4CWQ/ref=asc_df_B06XXW4CWQ5201806/?tag=hyprod-20&creative=395033&creativeASIN=B06XXW4CWQ&linkCode=df0&hvadid=216512288342&hvpos=1o4&hvnetw=g&hvrand=11218286639866080818&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9004882&hvtargid=pla-349069239329 (https://www.amazon.com/dp/B06XXW4CWQ/ref=asc_df_B06XXW4CWQ5201806/?tag=hyprod-20&creative=395033&creativeASIN=B06XXW4CWQ&linkCode=df0&hvadid=216512288342&hvpos=1o4&hvnetw=g&hvrand=11218286639866080818&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9004882&hvtargid=pla-349069239329)
Title: Re: induction heater for 3d printer(600 C)
Post by: T3sl4co1l on October 05, 2017, 05:27:56 pm
You cant 3D print metal the same way as plastic because it goes liquid when it melts instead of gradually softening like the plastic does

Depends on alloy.  Pure metals and eutectics melt suddenly.  Everything else has a "mushy" range.  This is critical to most casting alloys, where the molten metal is poured into a mold, then allowed to freeze.  As the metal freezes and shrinks, from the surface inward, molten metal is pulled into the part through thicker sections (that are added, intentionally, to feed this demand).  This prevents the formation of holes or voids.

Even with a eutectic alloy, careful manipulation and controlled melting can give excellent results.  Anyone who has crafted a sculpture out of solder in their free time understands this. :)

Also, some basic ideas:

https://www.youtube.com/watch?v=sFXniBbgbw0 (https://www.youtube.com/watch?v=sFXniBbgbw0)

Mind steel is basically eutectic, so that's something to think about. :)

https://www.youtube.com/watch?v=y9pknU0zv9c (https://www.youtube.com/watch?v=y9pknU0zv9c)

Tim
Title: Re: induction heater for 3d printer(600 C)
Post by: free_electron on October 05, 2017, 05:37:34 pm
thanks friends :)
 induction heater ... hard plastics.
look up 'induction' ... you are talking nonsense
Title: Re: induction heater for 3d printer(600 C)
Post by: T3sl4co1l on October 05, 2017, 06:07:03 pm
thanks friends :)
 induction heater ... hard plastics.
look up 'induction' ... you are talking nonsense

Incidentally, the alternative -- dielectric heating -- isn't going to work for plastics of arbitrary size and shape.  You need good contact to the material being heated, like rollers feeding sheet.

Tim