What is the reverse 3d printing process?

Question

3D printers

Hello, I'm interested in materials on the topic of reverse 3D printing technologies, when we evaporate / remove materials layer by layer while preserving the original material. Those. it should be close to recycling. For example, from an aluminum can you can get granulated or powdered aluminum, from a glass bottle you can also get only glass.

Google did not help, apparently, not so I ask.

Answer 1

CNC milling machine ?

Answer 2

There are no technologies that can equally disassemble complex objects.
You can collect plastic in a pile, melt it.
Glass can be broken into small pieces and melted down.
You can cut a tree into crumbs, compress it with glue, and so on.
But the most difficult thing in this is the purification of impurities. This is always a unique process for each case, if such a case is implemented in the industry.
And in layers - well, there is layer-by-layer milling, and there is layer-by-layer scanning in different ranges. All.
The molecular analyzer is still only in books. Fantastic.

Answer 3

That's not how you ask. The process of reverse 3D printing is milling. But to turn an aluminum can into aluminum dust, this is already from another opera. I think that an industrial shredder will cope with this, which will crush the material in stages, reducing the fraction.

Answer 4

Grinding / grinding is really :)
True, you can’t get powder metal like that.
And about the layer-by-layer removal of material from the workpiece, to obtain the product - milling, turning, and other subtractive manufacturing methods