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I'm wanting to create a perforated piezoelectric disc for use in creating a solid state aeroponic mister. The water droplets, and thereby the holes, can only range in size from 5-50 micron in order for the plants to efficiently absorb the nutrients.

I've attempted to puncture holes by hand using tiny needles in the past but since the discs are extremely fragile my attempts were never successful. I noticed this 0.03mm (aka 30 micron) drillbit set on Amazon and I was wondering if I were to use a drill press with this bit if I would be able to perforate the disc without it shattering? Has anyone else tried this or would you happen to have a better solution?

Drill bit set: https://amzn.to/3tH9uDb Commercially perforated disc: https://amzn.to/3esbMQb

While I can purchase commercially fabricated discs I want to have the ability to create a disc of any shape and size myself which is why I'm looking to pursue the DIY route. I know this is probably more technical than most questions posted here and I apologize for that. Since there isn't a community for material science or machining here this was the closest thing I was able to find. Any help would be deeply appreciated. Thank you :)

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This has all the markings of an Engineering SE question.

According to a number of websites, American Piezo included, the commercially produced product is composed of various materials, but include a ceramic/crystalline component.

A traditional piezoelectric ceramic is a mass of perovskite ceramic crystals, each consisting of a small, tetravalent metal ion, usually titanium or zirconium, in a lattice of larger, divalent metal ions, usually lead or barium, and O2- ions.

One can expect the ceramic/crystalline component is what contributes to the brittle characteristic of the material. Traditional cutting tools are likely to create as much damage as the attempt to puncture created.

A carefully controlled water jet may be able to create a hole, but the size is not likely to be as small as you desire. According to Accurate Water Jet, you can get holes in 3 mm material as small as 500 microns but the diameter is not going to be consistent. The process involves forcing high pressure water with abrasive directly at the surface, which results in spray back along with a sideways vector, abrading the upper portion of the hole. The size is outside of your requirements, which makes this an exercise in futility.

Abrasion applied by a rotating object may be a solution. I've read of glass being cut by copper tubing. The tubing is placed in a drill press, a dam of modeling clay constructed around the desired area and water with abrasive poured into the dam. Light pressure and repeated lifting allows fresh abrasive along with cooling. It's not fast, but broken glass is akin to broken ceramic piezo disks.

About the best DIY method you can try would be similar. Buy the tiny bits, but grind the tip flat. Build a dam, load it with jewelers rouge in water suspension and dab away. If you are using an ordinary drill press, consider that the run-out for such a machine may exceed the diameter of the bit. This will result in a larger hole and/or destruction of the bit.

How to determine amount of pressure? Use my favorite method for tightening a screw: apply torque until it snaps, then back off a quarter of a turn. Seriously, too little force will get you farther than too much, for obvious reasons. You aren't trying to force the bit through the ceramic. You're trying to apply the rouge to the disk while it spins.

High speed means higher heat, so a moderate rpm is indicated, along with the light pressure.

In response to OP comment:

I own a CO2 laser and for some reason neglected to consider that as an option. I can create a hole in plywood approximately 0.110 mm, which is still larger than your requirement. I can create similar holes in glass which has properties similar to ceramic and vice versa. Returning from a test moments ago, I've discovered the laser will create coning in a manner similar to that expected of a water jet. The laser creates microscopic fracturing caused by the heat of the laser being absorbed by the glass. In a pane of ordinary window glass, the upper surface was approximately 1.50 mm in diameter when the laser reached the lower surface. The hole in the lower surface was 0.50 mm in diameter.

Diode lasers, which have a lower cost than CO2 lasers will not impact glass due to the different frequency of the beam. The focused beam of a diode laser is rarely a circle or square shape and would not provide a suitable hole either way.

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  • Thank you VERY much for your informative response. Would it be possible for me to create the holes in the ceramic material using some kind of laser setup either off of Amazon (or somewhere else) for a "reasonable price" or perhaps by making a DIY laser myself either from scratch or modding an existing one that would be capable of this task? – at0micV3n0m Apr 18 at 18:22
  • Added response in main post. – fred_dot_u Apr 18 at 21:32
  • Wow, I REALLY appreciate you taking the time and effort to run that experiment with your laser. I truly can't thank you enough for that. It saved me a LOT of time and money by not having to order one just to learn that it wouldn't be adequate for this project. – at0micV3n0m Apr 18 at 23:36
  • I reposted this question on Reddit and someone suggested 3D printing a piezo disc using a "piezoelectric material." The only ceramic printers I'm aware of are SLA based but even so there are still individual layers. My concern is that by operating the piezo disc at over 1khz continuously indefinitely the layers will being to peal themselves apart from each other. Do you have any experience working with 3D printed ceramics and is this a valid concern? Thanks again for all your help. It's deeply appreciated :) – at0micV3n0m Apr 18 at 23:39
  • Part of what makes a piezo crystal function in the manner it does is that it is crystalline. I have no experience with printing ceramics, but I suspect the process would destroy any crystalline structure. I know of no SLA based ceramic printers. Most of the hobby grade ceramic printers are extrusion type. – fred_dot_u Apr 20 at 9:07

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