Expected lifetime of implanted magnets?

I have been considering getting a magnetic implant, but one main concern has stopped me.
How long would magnets such as the m31 or m36 (from dangerousthings.com) live?
Would they have to be replaced every five years or so?
As we all are aware permanant magnets eventually become demagnetized.
The last thing I want is a demagnetized piece of useless metal in my hand.

Comments

  • I think the problem with neodymium magnets isn't them just randomly demagnetizing (I'm pretty sure they last hundreds of years unless exposed to high [~300°] temperatures or damaged), but rather that when the coating fails the magnet starts breaking down within your body- becoming demagnetized and encapsulated in scar tissue.

    I read something Brian Decker said on his Instagram a while back where he said almost all coatings eventually fail after about three years or so. I know many have had them last longer, but he's implanted a lot and that's his experience. (He implants parylene coated magnets, fwiw).

    This is one of the reasons why we are still experimenting with new biocoatings.
  • If the coatings all fail after about three years, then could you replace a degraded magnet with a new one in the same spot? Or would you need a new implantation site?

  • I believe you can use the same location providing there isn't too much scar tissue. Since parylene does tissue bonding, though, extraction might be more damaging than implantation.
  • What would be the best way to avoid scar tissue? Because unless it fully heals in three years and there is no scar tissue. The places you could put a magnetic implant would decrease with every new magnet as would sensitivity. While I have faith in science. completely bio-compatable coatings might be 5-10 years away if not longer.

  • Titanium shells should last a lifetime and provide perfect biocompatibility. I have not received any replies from companies providing the required laser-welding service.

  • Yeah. While I agree with Decker.. The ideal magnet should last a lifetime.
  • Hmm. Titanium can't be that hard to come by. Why do you think they've not replied? Surely there have to be a few ways to get them. Also. Wouldn't the laser-welding heat the magnet to a point where it might become inert? Or would it be precise enough to avoid that?

  • Titanium and other bio-compatible coatings are expensive to produce, I have a source of N55s with a 12 micron thick titanium coating and other coatings like biocompatible aluminum but, costly and is going to require a significant investment just to get samples for testing so I have a few more details to iron out before I decide whether or not to order samples.

  • @Darlokl17 titanium in such small quantities is very affordable. The setup and tooling costs are high and the numbers we need them are very small. Laserwelding is precise enough to weld even 20μm thin wires. Properly done the magnet would be nowhere near suffering damage.

    @Crucible I was talking about actual solid metal sheets , formed into cups, welded together around the magnet. With the metal having a thickness of somewhere between 50μm and 200μm.

    Biggest problem is to find someone with the right equipment and get a sample (or collect enough money to make a specialist laser welding company to take the job)

  • @ThomasEgi
    @Crucible I was talking about actual solid metal sheets , formed into cups, welded together around the magnet. With the metal having a thickness of somewhere between 50μm and 200μm.

    Biggest problem is to find someone with the right equipment and get a sample (or collect enough money to make a specialist laser welding company to take the job)

    The source I am negotiating with uses a sealed 12μm titanium foil, still working on details.
    As for laser welding, I can check my connections (I am a welder) and should be able to find someone who knows someone among machinists and millwrights who can perform the welding for a case of beer (universally accepted form of payment for favors among tradespeople).
    Also from checking out laser welding vids, I would say it would probably be cheap and easy to build a laser welding machine designed specifically for the purpose, maybe start with a USB laser engraver $70, swap out the laser $15-20, adjust the power supply internally and set it to run for a set period of time, set the magnet in a mini lathe $60 and some type of wire feeder for filler, easier and better results than autogenous welding.
    The cheap, easy to build welding machines functions a lot better than manufactured machines but lack in ability to change settings without going in and messing with the internals.

  • @Crucible said:

    @ThomasEgi
    @Crucible I was talking about actual solid metal sheets , formed into cups, welded together around the magnet. With the metal having a thickness of somewhere between 50μm and 200μm.

    Biggest problem is to find someone with the right equipment and get a sample (or collect enough money to make a specialist laser welding company to take the job)

    The source I am negotiating with uses a sealed 12μm titanium foil, still working on details.
    As for laser welding, I can check my connections (I am a welder) and should be able to find someone who knows someone among machinists and millwrights who can perform the welding for a case of beer (universally accepted form of payment for favors among tradespeople).
    Also from checking out laser welding vids, I would say it would probably be cheap and easy to build a laser welding machine designed specifically for the purpose, maybe start with a USB laser engraver $70, swap out the laser $15-20, adjust the power supply internally and set it to run for a set period of time, set the magnet in a mini lathe $60 and some type of wire feeder for filler, easier and better results than autogenous welding.
    The cheap, easy to build welding machines functions a lot better than manufactured machines but lack in ability to change settings without going in and messing with the internals.

    If you are willing to actually look into how you can weld the titanium casing I can assist you. I have many methods of testing the efficacy of the biocompatible layers, and others ex Cassox may be able to help with the actual casing as that's his realm of expertise.

  • @ThermalWinter I won't be making the welding machine, just mentioning that it's a feasible option and I am able to perform visual inspections via images from a microscope and provide directions for better weld performance. I am focused on dealing with magnet suppliers that are able to apply the coating themselves.
  • OemOem
    edited March 2018

    @ThomasEgi said:
    Titanium shells should last a lifetime and provide perfect biocompatibility. I have not received any replies from companies providing the required laser-welding service.

    Why would a titanium shell last longer than a Titanium Nitride shell?

    Edit: (I should have done any research) but my point still stands. TiN doesn't corrode over time for no good reason. At least according to wikipedia, the corrosion is brought on by repeated mechanical stress. Basically, the finger is the worst place in the world for an implant to try and have a long lifespan. Any coating has the problem of being worn down by the repeated stress of finger use.
    Good link. This article has some very nice info on the fatigue rates of different biomaterials. Titanium rates all around lower than its alloy counterparts. I think a pure Titanium shell is the wrong direction. It sounds chemically simpler than TiN, sure, but just because we feel safer because it's common sense that Titanium is inert does not make Ti >TiN. I think we need to explore more options like thicker coats and different containment options.

  • @Oem If you want to examine Ti alloys, β-Ti3Au seems like it'd be ideal, though I can't find any info on it's strength values, so there might be difficulties forming it to capsules.

  • Keep in mind you'd have to weld those capsules. Mechanical strength and biocompatibility isn't the only factor here.

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