EPlus3D Customer 3D Prints Metal Cochlear Hearing Aids

3D printing is the dominant technology in the hearing aids industry. But so far not a lot of people have thought about cochlear hearing aids as a potential market. Cochlear implants are a series of devices working in concert that pick up sound, organise these sounds, turn them into electric impulses, and then interfaces with the auditory nerve. They can in part give someone a semblance of hearing in cases where it is absent or difficult.

An Eplus3D customer used their EP-M260 powder bed fusion 3D printer to make Ti-6Al-4V titanium cochlear implant components.  The EP-M260 is a 266 x 266 x 390 mm³ build volume, dual laser PBF system with optimised powder feeding and recycling. The ear was scanned and a design for a hearing aid shell was made based on that. Then the 3D printer makes a total of 150 of these shells per build with a 30μm layer thickness. The print job takes 30 hours, using 450 grammes of material at claimed total material cost of $400. The prints are then wire cut off the build plate, smoothed, and in ten minutes each of the shell’s support structures is removed. A batch then takes 30 hours to be polished. The company claims that each shell costs 25 yuan, which would be less than $4. The price makes this exciting enough in and of itself. Although we must remember that we don’t know the labor rate and depreciation the company used to get to this calculation. But, all in all, lovely number.

The company says that it can make 0.2 mm thin walls, making the implants half as thin as polymer alternatives. This makes the implant smaller. Eplus3D also says that the ¨matching success rate of the deep ear canal products is increased by 64%.¨ The internal hearing aid also has more space for receivers and the like.

We usually think of 3D printed polymer replacing metal, but there could be other cases out there where 3D printed metal could replace polymers. It is notable that the wall thickness was the major reason why metal was chosen here. Larger internal volume is also a very important part of this, as it would really let companies do more inside of a similarly sized implant. Similar considerations could mean that for some wearables, headphones, and small electronic devices, metal 3D printing could be a real alternative. Assuming that Eplus3D can really make these shell components for less than $4 consistently, then the company could really expand what it could make.

We’ve always been focused on high end applications at high cost, usually for high mix low volume manufacturing. We haven’t minded paying more for machines that worked well. We also didn’t mind paying more for powder if we wanted it to work well as well. But, now that we’re looking at more high volume applications, price is increasingly becoming more of an issue for us. New technologies such as Seurat or binder jet promise to replace power bed fusion by being cheaper. But, what if lower cost machines are really the answer? I’m a big fan of One Click Metal and other inexpensive powder bed companies. I really think that for a lot of applications, powder bed fusion could become much more cost competitive through lower-priced machines and materials pricing. There is still of course a place for high volume systems with high reliability for crucial parts, but there could also be a market out there for machines capable of making customised titanium hearing aid shells for $4.