Powder metalforming - GIF

[ToolTalkBot]

Powder metalforming.




Previously:

Metal powder compacting press - GIF
Powder forging and pressing - GIF
Powder pressing gears - GIF
Pressing powdered metal slabs - GIF

[albertq]

What kind of metal fuses together so easily? Lead?

[lavern s]

I don't know exactly what kind of metal fuses together so easily, but that part is probably fairly easy to crush until it goes through an oven and extended heating process. My cousin owns a "Powdered Metal Manufacturing" company and I was given a tour of the operations there. Truly amazing what they make with that process. One of the most interesting parts I saw was a connecting rod which after pressing and heating came out ready to be installed with no machining required on the bearing fits. They did need to tap the threads I believe, but then again that was about 10 years ago and I am sure the technology has already improved to be even more capable.
LaVern

[mwmkravchenko]

What kind of metal fuses together so easily? Lead?

Steels, tool steels, Bronze, Titanium, many many metals. Off to the Pizza Over to make them solid. At this point they are not hard like metal.

Mark

https://en.wikipedia.org/wiki/Powder_metallurgy

[Elizabeth Greene]

Most Tungsten carbide inserts are made this way, e.g. the ones used for lathe and mill tooling, as well as the buttons on tricone drilling bits.

If you take apart a cordless power tool or a kitchen mixer, there's a very good chance the gears inside it are made this way.

The just-pressed parts are called "green" because they are still crumbly. They go into an oven, either under a vacuum or inert gas, and are "sintered" (cooked) to make the powder bond permanently together. The strength of the finished parts varies on the quality of the powder, press pressure, press technique, sintering process, and powder composition. They are generally stronger than cast parts, but weaker than forged or machined parts. After the dies are made, they can be made much faster than (and at a fraction of the cost of) cast, forged, or machined parts.

It's called "Powder Metallurgy", and I hope I get to play with it once I get my new mill up and running.

[albertq]

It's called "Powder Metallurgy", and I hope I get to play with it once I get my new mill up and running.[/QUOTE]

I understand how the Powder Metallurgy process works but have never seen it being used first hand. Referring to video clip, I was surprised to see what looked like fused metal chips squeezed out the top. Would all powdered metals squeeze out like large metal chips?

[Elizabeth Greene]

In this video they overfilled the mold, and that's the squeezeout. I've never seen that before; most molds are designed to catch only the exact amount of powder required to make the process more controllable and economical. I've also never seen a rotating mold before, and suspect this might actually be casting graphite or SiC crucibles instead of metal.