<p>I am currently printing PLA infused with 80% copper powder. So far I mainly used it because it looks and feels really nice and post-processing is almost limitless, however recently I have thought that metal-like filaments might actually be a good idea for gears (in case I don't want to use polycarbonate or carbon fiber PLA).</p>
<p>I have been researching about the material properties of copper-infused PLA and found a few studies about the &quot;strength&quot;, however, those seem to have exclusively focussed on how much weight can be suspended on a hook where it showed pretty good results. The only other info I found was an unsourced &quot;it is more brittle&quot;, however the objects I printed so far do not feel more brittle.</p>
<p>Does anyone have any experience with spur gears printed from copper-infused PLA? Are there any advantages over regular PLA? Any downsides (I could imagine higher abrasiveness is not really helpful)?</p>

[{'answer_id': 18717, 'author': 'Criggie', 'author_id': 12956, 'author_profile': 'https://3dprinting.stackexchange.com/users/12956', 'pm_score': 1, 'selected': False, 'text': "<p>At a guess, copper really isn't that strong so you're likely to see minimal improvements, if any.</p>\n<p>The PLA carrier plastic is still PLA, with a low melting point.</p>\n<p>The copper won't &quot;fuse&quot; with the PLA, it will still be flakes of metal embedded in a tiny pocket inside of a plastic structure.</p>\n<p>However this is all speculation, and your best option for an answer is to print some gears and methodically test them against plain PLA, and perhaps a metal gear if you can.  Try and use identical setups/bearings/pressures and times.</p>\n<p>Perhaps a high torque and a high-speed test, in both lubricated and unlubed, for PLA, copper-PLA, and a straight metal gear? That would be 12 tests in all and clear out all questions.</p>\n"}, {'answer_id': 18730, 'author': 'Trish', 'author_id': 8884, 'author_profile': 'https://3dprinting.stackexchange.com/users/8884', 'pm_score': 2, 'selected': False, 'text': '<p>With the right material, you could print the gear and then sinter it, resulting in actual metal gears. However, 80\xa0% metal-filled PLA is at the lowest border to achieve this, and a lot of that technology is patented.</p>\n<h2>Filamet<sup>TM</sup></h2>\n<p>Filamet<sup>TM</sup> is a <a href="https://shop.thevirtualfoundry.com/" rel="nofollow noreferrer">Virtual Foundry</a> product that contains around <strong>80-92\xa0%</strong> metal powder of 100-400\xa0µm particle size, suspended in a carrier. The carrier material is supposedly PLA or at least functionally similar. The resulting filament is highly abrasive, requiring stainless steel<sup>1</sup> to print more than short sections. The high metal content also gives the material a <em>memory</em> of its spooled-up shape. This demands extra special treatment during printing to prevent snapping the filament in the shape of a pre-heater to get it spooled off properly. The same company also offers similar products for ceramics. After printing, the models are burned-out and sintered in an oven at very high temperatures. This sintering is done in a crucible filled with carbon and alumina, burning out the PLA carrier while retaining the shape. Their material-making process is <a href="https://thevirtualfoundry.com/2019/11/21/the-virtual-foundry-wins-a-patent-for-the-process-used-to-produce-its-extrudable-plastic-infused-materials/" rel="nofollow noreferrer">patented</a> <a href="https://www.freepatentsonline.com/y2018/0193912.html" rel="nofollow noreferrer">(patent itself)</a> and covers all their metal, ceramic, and glass materials.</p>\n<p><sub>1 - or something even more hardy, like an <a href="https://web.archive.org/web/20210707122849/http://olssonruby.com/" rel="nofollow noreferrer">Olsson Ruby</a> by <a href="https://3dverkstan.se/" rel="nofollow noreferrer">3DVerkstan</a></sub></p>\n<h2>MetalX<sup>TM</sup></h2>\n<p>The MetalX<sup>TM</sup> system by <a href="https://markforged.com/" rel="nofollow noreferrer">Markforged</a> uses a special printer and proprietary <em>Bound Powder Metal Filament</em> that contains an unknown plastic binder. A lot of this machine and surrounding peripheries are <a href="https://markforged.com/patents" rel="nofollow noreferrer">patented</a> and information spare. Among others, their <a href="https://patents.justia.com/patent/10076875" rel="nofollow noreferrer">method of creating composite filaments</a> and their <a href="https://patents.justia.com/patent/10377083" rel="nofollow noreferrer">binder material, support material &amp; sintering process</a> are only described in patents. From their advertisement I could deduce the following process: The MetalX printer prints the item with unknown print settings, resulting in a raw item containing metal and the binder. After wash-cleaning using a liquid known as Opteon<sup>TM</sup> SF79 <a href="https://www.opteon.de/-/media/files/opteon/opteon-sf79-cleaning-fluid.pdf?rev=082d2f050b3440e8b47f8dd9b58324a9" rel="nofollow noreferrer">(Datasheet)</a> to remove the specialty binder, the sintering happens in a free oven at 1300\xa0°C, leaving behind a metal product. Free oven means here, that the printed part is not embedded in a filled crucible like with Filamet<sup>TM</sup>.</p>\n<hr />\n<p><sub>Disclaimer: I am not affiliated with either Virtual Foundry, Markforged, 3DVerkstan, any of their products or affiliates.</sub></p>\n'}]
['https://3dprinting.stackexchange.com/questions/18713', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/20301/']