Engine Hypotheticals

[Gatecrasher]

Yes, you can google semiconductor manufacturing, all of the technology required is potentially there already, you just need Billions of dollars to build a plant. Atomic Layer Deposition has also been about for a few years, so yes that is why it would take time if you went about this method. There are however technologies from the 80's that deposited micron level films in less than 30 minutes, they could be adpted to work.

[superdread]

Yes, you can google semiconductor manufacturing, all of the technology required is potentially there already, you just need Billions of dollars to build a plant. Atomic Layer Deposition has also been about for a few years, so yes that is why it would take time if you went about this method. There are however technologies from the 80's that deposited micron level films in less than 30 minutes, they could be adpted to work.

While you can deposit films at high thicknesses, your photolithographic process limits your effective thickness. The imprint the light leaves in the lacquer is wider at the top than at the bottom (because the thermal energy absorbed decreases with depth).

Writing the patterns on the lacquer would require either a set of masks (one for every layer and every material, so millions) or direct electron (or ion) beam writing (which takes a lot of time).

Then, again, the problem of microstructure. There are processes for affecting the structure of metals you need to redevelop them for every new material. Also the boundary surfaces between the different layers limit the maximum grain size.

So it's more like tens of billions to develop the processes and machines, billions to build a plant and every engine would take years to build (and cost many many millions).

[olefud]

I don’t see the actual photolith process as being of use. It’s severely limited in the Z axis in that it utilizes acid etching that undercuts vertical etched surfaces. For printing plates, which required “vertical” faces, a substance known as dragon’s blood was used to protect the vertical surfaces but which washed away with an aggressive spray on the horizontal surface. PC boards have rather thin copper that’s etched and of course ICs are micro scale.

Most 3-D articles I’m aware of are formed by adding powdered metal or plastic and sintering the powder with light, i.e. laser, IR etc. This is just for form or fit but has limited structural properties.

To my knowledge not even an engine component is produced with this process, let alone an engine. Sintered conrods have been used for production engines, but they are hot pressed from powder to near net prior to sintering.

Extrapolating from current technology, unitary cast as a whole engines are at best a government project.

[superdread]

I don’t see the actual photolith process as being of use. It’s severely limited in the Z axis in that it utilizes acid etching that undercuts vertical etched surfaces. For printing plates, which required “vertical” faces, a substance known as dragon’s blood was used to protect the vertical surfaces but which washed away with an aggressive spray on the horizontal surface. PC boards have rather thin copper that’s etched and of course ICs are micro scale.

Do you mean the that you cannot etch a straight trench? Like so:

(left one for monocrystals, right for polycrystals, image property of el-cat inc.)

There are techniques to kind of work around that:
etch a little bit => pour photoresist into the hole => re-expose => etch developed photoresist from bottom of trench => start over

Most 3-D articles I’m aware of are formed by adding powdered metal or plastic and sintering the powder with light, i.e. laser, IR etc. This is just for form or fit but has limited structural properties.

To my knowledge not even an engine component is produced with this process, let alone an engine. Sintered conrods have been used for production engines, but they are hot pressed from powder to near net prior to sintering.

Extrapolating from current technology, unitary cast as a whole engines are at best a government project.

I'm not disputing that rapid prototyping of the extend to build a working engine is very far fetched and wishful. The metallurgic quality is simply not reachable in any feasible manner. As the pay-offs are not great and the disadvantages (e.g. not being able to open or repair the engine) outweigh them by quite a bit, we will not see that development in years to come.

Almost all parts in an engine are simple in their structure, so the gained strength from machining them from properly treated materials (forged, ...) is better than cooking them from some powder. That said, the exhaust manifold could be something where rapid prototyping could enable more complexity and speed of manufacturing.

[Dragonfly]

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Most 3-D articles I’m aware of are formed by adding powdered metal or plastic and sintering the powder with light, i.e. laser, IR etc. This is just for form or fit but has limited structural properties.
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Some time ago I came across a video on YouTube which showed what I understood a process of forming a complex product (a hollow sphere with holes over the surface) from liquid photo polymer. The laser beam was acting from beneath a transparent tank forming layers and the sphere was gradually lifted up as layers formed until the whole of it was up in the air.
This is just an example of using other material than powder but inapplicable IMHO in engine (or metallic parts) production. But maybe good for making complex die cores.