Powder optimized for AM? Really?

There is an increasing number of independent powder manufacturers marketing metal powders towards the AM community. This is basically a good sign. For a long time, AM machine manufacturers have insisted that their ”original powders” are the only safe choice. Sooner or later, this situation must change. If you buy a new car, you expect it to run on gas bought at any petrol station. Automobile manufacturers do not command people to use their branded gasoline.

But anyway, I get confused when I see third-party powder suppliers marketing their powders as ”Optimized for AM”. What does optimized mean in this context? Does it simply mean that their powders are spherical? Does it mean that their powders have a size distribution similar to the ”original powders” offered by machine manufacturers?

In my humble opinion, a metal powder is optimized for an AM process only if it has been experimentally tested and verified to work in that AM process. Additive manufacturing is not yet at a stage where you can predict the processability of a powder just from some simple laboratory test data. To claim that a powder is optimized, you have to test the powder in your AM process.

Next time a powder manufacturer tell you about their ”optimized” AM powders, be skeptical and ask questions. What process? What machine supplier? What geometries? What process parameters? What material properties? In many cases, you will realize that their powders have not been tested experimentally. ”Optimized” is often an empty marketing phrase only.