A few weeks ago, a reader sent us a photo of a 3D printer that’s been turning out metal injection moldings, a process that involves the injection of molten metal into a mold, which in turn creates a metal surface.
This particular printer is 3D printing an aluminum alloy called Alumina, and the first batch of its prints have been in production for a few weeks.
The process is quite a bit more complex than just popping a bunch of aluminum parts together, though, and it requires some basic knowledge of how the process works.
In a nutshell, it involves a mixture of hot liquid and an acid solution that’s then pumped through a mold.
Once the liquid is flowing, the hot liquid pushes against a substrate and the acid dissolves the substrate, creating a liquid metal.
The resulting powder then sits on top of the mold, forming a hard, porous surface.
In other words, the process creates a powder that has a hard surface.
It’s a process known as a mold casting, and its name comes from the process of forming a mold that’s hard to break down and dissolve in water.
This process is actually quite simple, though.
When you want to make a molding for a metal that’s harder than the powder, you simply pour a bit of the hard-to-break-down powder into a mixture that contains a mixture (such as alumina or aluminum) that has been heated to a specific temperature.
The mixture is then heated and the temperature of the mixture is raised, so that the mixture becomes more and more solid as it cools.
The heat generated by the mixture increases, so the mixture expands, forming an outer layer of solid metal.
Once you have the solid surface of the metal, you add a few more layers of solid material on top, and you’ve created a mold (or “factory” if you prefer).
When you’re done with the process, the metal is then cast into a metal mold, and once that’s done, the final product will look like this: