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Anyone interested in solid titanium encapsulated magnets?

For years, the community has been struggling to produce the "perfect" implantable magnet. This may not be the perfect one either, but it might be a promising step into the right direction. Recently I've been stumbling across a number of different companies which do laser welding of pure titanium for medical applications. These companies can work with very thing titanium, typically down to 50μm, some even lower than that.

As you probably guessed by now, the idea is to have two tiny cups of titanium to tightly fit around a magnet and weld the seam shut with a laser.

I ordered a sheet of 0.1mm thin titanium to experiment with. I used a hole punch to get small circular pieces and then hammered a metal the piece with a metal rod into somewhat-softish plastics to get a shell which fits the magnet. Unfortunately I was a bit off center but none the less here are the Pics of my old parylene coated 4mm neodym magnets and one half of the shell:

1. Magnet&Shell
2. Magnet inside the shell
3. Sideview

As you can see it's not a perfect fit yet, but pretty close for a 5 minute job. A proper die to press/punch the titanium into shape would be required but that's nothing too crazy. Although thin, the titanium shell is pretty hard/solid. Material thickness is equal to thin razor blades and it takes quite some force to dent/cut/crack this. Laser welding itself is done under argon-gas atmosphere, so there should be virtually no moisture inside the shell left.

The pro's and cons:
+Titanium - 1st class biocompatiblity
+Solid, robust shell, less prone to failure compared to coatings
+Protects both, magnet and body
+Moisture barrier, no humid environment for the magnet to degrade
+virtually no thermal stress for the magnet (laser welding heats only very locally, the magnet itself is pretty much untouched)
+Produced by companies doing medical instrument work on daily base (they are all based in Germany)
+Well controllable production process.
+does not require mass production, at least in theory small number runs should be possible
+mass production could be cheap ( producing shells can be done using stamping, welding takes only seconds)
-prototype costs not known

So long story short. How many of you would be interested into getting hands on one and how much would you be willing (worst case) to pay for it.
Not that I intend to rip anyone off but I sort of need some numbers to approach these companies with. 


Displaying comments 1 - 30 of 39
  1. Ooh. Unfortunately I haven't got the resources yet to implant. Otherwise I'd be in.
  2. I've got all the tools to implant, would be  interested to test it out.
    I have no real idea on how much it would go for, if it does end up working out great i'd say most i'd pay for one is 30-45.
  3. If the performance exceeds a Haworth magnet because of the thinner coating, I would pay $100, the same as a Haworth magnet. Since these don't have a proven track record of safety I would side with @alsike and say $30 - $45 for a prototype.
  4. I would be interested in testing these out, this sounds to me like the best shot at getting a viable magnet so far. I'd be down for $30, maybe more if needed.
  5. This sort of matches my expectations. So we'd have demand for like 5 magnets for testing at 30$ each. Not exactly the job to make such a company do backflips of joy but it's something to approach them with. Thx for the feedback so far. Others are still welcome to add if they want to.
  6. I would also join in with 30€  - lets give it a try since TiN is on ice.
  7. Does the Ti interact with the magnetic field in any negative way?

    If it works, I'd be down to get one.
  8. I'd try it like.

  9. I couldn't implant right away, but if the performance is as good or better than Haworth magnets, I'd be amenable to a magnet priced at whatever the base cost of the magnet was plus whatever fraction of the manufacturing few the magnet accounts for, and maybe another 10-20% of whatever the costs to that point were.
  10. You need to heavily cosider galvanic corrosion. The neodymium will have long term galvanic corrosion when it is in contact with another noble metal. The effect is exponential depending on your anode/cathode ratio and the difference in nobility between the two metals.

    Galvanic corrosion between neodymium and the outer layer is a massive long term concern. This is the one reason I am using Ni/Cu in my magnet. You also need to heavily consider how you will accurately test these magnets for biocompatibility. There can be a divot 1/2 micron across that can cause a rejection and you have to be able to test that before offering these to other people.

    I think you may have to spend some time considering how you can guarantee the safety of each individual and how you can guarantee each person that invests gets a magnet. If you legitimately want to help make high quality biocompatible magnets pm me and we can work on this project together.
  11. @ThermalWinter Titanium immediately builds up an oxide layer when exposed to air which is the reason why it's hardly interacting with anything despite the fact that it's highly reactive. So chances are the neodymium will be in contact with a pretty darn good insulator. If you'r still worried a piece of kapton tape should do the trick.
    Thx for all the replies so far.

  12. I'd definetely throw in like 30-50 euros. I'm native german so I could help out if something like translations are ever needed dealing with the companies here.

  13. @Aeris, Titanium does not interact with static magnets. It's conductive so you can get small eddy currents if your ... dunno. hold your hand over a miniature linear actuator or so. Long story short: no. It's basically like aluminum.

    @ThermalWinter I thought about it a bit and I'm pretty sure titanium is not noble at all. Not sure if galvanic corrosion would be a problem for 100μm thick metal to begin with. Quite some material to corrode away.

    So far there seems to be enough interest for a small run of 10. I'll try contacting the companies during the course of this week and see what they have to say.

  14. Titanium is not a noble metal according to wiki:

    BTW, just to avoid any confusion when I say I don't have resources to implant I really don't (don't even know anyone to do it for me, aside from tools etc). So sorry to have to say this but don't count me as a "demand" at this point in time (and possibly in the next couple of years).

  15. I have exactly $42 in my paypal right now. Would happily send it for one of your magnets!

  16. i am a medicine student from india
    an uk based company is already selling biocompatible, hypoallergenic, titanium encased 12000-14000 gauss neodymium magnets but, they are big in size and cannot be implanted in fingers but, they can be implanted in palm or wrist or some other suitable area in body
    we can contact this company to make biocompatible magnet encased in implant grade titanium or i would prefer the magnets to be coated in titanium gold because titanium gold is even more biocompatible beside that titanium gold is a magnetic material it can be magnetised it is attracted to magnets so it will protect the magnet from loosing its property

  17. titanium gold itself can be magnetised but it wont match the strength of a neodymium magnet

  18. I'd be in. Let me know what I would need to contribute to own one of these.

  19. Have you had any luck finding a manufacturer?

  20. I was wondering what the status was on this too. I should be able to throw in for two.

  21. sorry guys. I started at my new job about a month ago and it turned out to be a very work-intense start. Once I get more than an average of 5h of sleep per day I'll try contacting a bunch of companies doing laser welding. I got those tabs open, just couldn't manage to find time to do it yet.

  22. No stress, no stress! It's far more important to take care of yourself and get stable than spread too thin and get into a really tight spot. x_x

    Congratulations on your new job. ^^ This will be here when you're ready, I'm sure people will remind you. Hehe. Watching patently, this really interests me.

  23. i contacted a company named BJAmagnetic they said they they can provide implantable titanium plated magnets at $750 per 100 piece
    a hearing aid named maxum uses tiny titanium encased magnet to be anchored around stapes in the middle ear
    there are number of other medical implants which use titanium encased magnets

  24. @ThomasEgi let me know of I can do anything to help.

  25. No worries! Take care of yourself first. I'm in no rush.

  26. I would also be interested in such a magnet. Especially if we could get it to closely match an m31. I could see paying $50-120 for something like that.

  27. I want one, but one much bigger than am M31. I really liked the 3mm X 6mm one I had for a short while...
    Also in for $50.

  28. I'd like to help if I can.

    EDIT: Send some here( and they will weld some to sample. I may try this myself.

  29. I could be interested in a prototype. The smooth "smartie" shape looks great for implanting smoothly. I'd want a little info on how well the titatnium holds up to, say, constantly being vibrated against, or beaten, or handling human juices for a while.
    Probably willing to pay in the 30-50 range if we have happiness!

  30. @Erischilde Titanium is a very robust material. Used in critical aerospace applications (due to mechanical strength and low weight) and has most excellent properties when it comes to implantation. It's the choice of material for many load bearing implants. It's lifetime within the body is virtually unlimited as the material itself builds up a protective biocompatible oxide layer every time it gets damaged (pretty much instantly).
    From my personal experience it takes quite a beating to get even a 0.1mm thin sheet in shape. My guess is your finger would be way beyond repair before you manage to significantly damage such a tiny titanium capsule.

Displaying comments 1 - 30 of 39