Qualifying an additive part means qualifying everything upstream of it

Properties depend on machine, powder lot, build location, orientation and thermal history. That makes the qualification unit a process, not a part.

By LasersNews Desk·21 Jul 2026·2 min read

Detailed view of a 3D printer showcasing components like wires, gears, and cooling fan. — Photo by FOX ^.ᆽ.^= ∫ on Pexels

Qualifying a machined component is well understood: material certification, dimensional inspection, and a manufacturing process that does not fundamentally alter bulk properties. Additive manufacturing creates the material and the geometry simultaneously, which invalidates that separation.

What varies

Machine to machine. Nominally identical machines produce measurably different properties owing to laser calibration, gas flow and thermal environment.

Powder lot to powder lot. Chemistry, size distribution and morphology vary within specification, and those variations affect the result.

Location on the plate. Gas flow across the build removes spatter and vapour, and it is not uniform. Parts at different positions experience different conditions.

Orientation. Layer-wise construction produces anisotropic properties. Strength along the build direction differs from strength across it, and fatigue behaviour differs more.

Build content. Thermal history depends on what else is on the plate, because heat from neighbouring parts affects local cooling rates.

That last point is the awkward one. A part's properties can depend on what it was built alongside, which means a qualified configuration may include the build layout.

What qualification therefore covers

Rather than certifying parts, additive qualification certifies a frozen process: specified machine, specified powder specification and reuse protocol, specified parameters, specified orientation and location, specified post-processing and heat treatment.

Witness coupons built alongside production parts provide per-build evidence, and any change to any element triggers requalification.

The cost consequence

That rigidity is why additive works economically in aerospace and medical for parts where geometry provides substantial value, and poorly where it is merely an alternative production route. The qualification cost is largely fixed per part number, so it amortises over volume but must be paid regardless.

It also explains why manufacturers resist machine upgrades and parameter improvements on qualified parts. A better process is not better if it costs a requalification campaign.

Where standards have helped

Industry standards for powder, process control and testing have reduced the burden by defining common requirements. They have not removed it, because the underlying coupling between process and material properties is physical rather than procedural.

This article was produced by the LasersNews AI desk and reviewed by our editors.