At PSI, we live in the details because in Additive Manufacturing, details decide everything.

We see it every day: perfectly engineered metal powders slowly drifting out of specification. A little oxidation here, a bit of contamination there, subtle shifts in particle size. Over time, powders that once built world-class components are written off as waste. Until recently, that was simply accepted as the cost of doing AM.

We didn’t accept it.

Our journey into powder rejuvenation is rooted in a simple belief: high performance and sustainability don’t have to compete. Fluidised Bed Reactor (FBR) technology sits at the heart of that belief, allowing us to restore powder performance at production scale, rather than discarding valuable material.

One alloy that perfectly illustrates this challenge is GRCop-42.

Originally developed by NASA for the extreme thermal and mechanical demands of rocket propulsion systems, GRCop-42 is no ordinary copper alloy. Designed to survive blistering temperatures while retaining strength and resisting oxidation, it has become a material of choice for rocket nozzles, combustion liners and other high-performance aerospace components.

Producing it, however, is anything but simple.

GRCop-42 relies on precise additions of chromium and niobium, elements that are difficult to incorporate into a copper melt and even harder to control during gas atomisation. Gas atomising GRCop-42 is exceptionally complex due to the alloy’s tightly controlled chemistry. Incorporating chromium and niobium into a copper matrix at the precise concentrations required is difficult in itself; retaining those levels through melting, atomisation and solidification is even more demanding. Both elements have limited solubility in copper and a strong tendency to segregate or oxidise if processing conditions are not exact.

PSI were backed by a US investor in the region of £800k to perfect the process parameters and develop the atomising technology to meet the NASA specification. There was at this time, only one other global powder producer who could officially meet the specification without altering the chemical composition.

The result is a narrow processing window. Small deviations in temperature, atmosphere or melt handling can lead to chemistry drift, oxide formation, or off-spec particle morphology. For producers, this translates directly into higher cost, lower yield and limited availability of qualified powder. Once produced, the value of GRCop-42 powder is therefore exceptionally high and making loss through oxidation during AM processing both economically and strategically unacceptable.

This is why effective powder recovery is not simply a convenience for GRCop-42 users, it is essential to the viability of the material in production environments.

In most AM environments, unused powder is repeatedly exposed to imperfect inert atmospheres. Over time, oxidation accumulates until the powder can no longer be used. For high-value alloys like GRCop-42, this has traditionally meant scrapping tonnes of material or settling for lower-performance alternatives.

This is where PSI stepped in.

Using our production-scale Flo-Bed® 235HT FBR, we now routinely recover GRCop-42 powders for rocket nozzle manufacturers. By fluidising the powder in carefully engineered reductant gas mixtures, we consistently reduce oxygen levels from around 900 ppm to below 400 ppm, comfortably within the specification of newly manufactured powder for a leading US rocket manufacturer.  

From a thermodynamic standpoint, copper oxides are relatively easy to reduce. But in practice, AM powders present a far greater challenge. Fine powders typically fall into Geldart Category C, meaning they are highly cohesive due to surface forces. Freshly reduced powders, with clean, oxide-free surfaces, can be even more difficult to handle. Achieving oxygen reduction without sacrificing flowability requires precise control of gas composition, flow regimes and pressure inside the reactor.

That control is where PSI excels.

Our work with copper doesn’t stop at complex alloys.

At PSI, we have also demonstrated exceptional results in the reduction of oxygen in ultra-pure copper powders, where tolerance windows are even tighter and performance margins even smaller. In these materials, even modest oxygen pickup can significantly impact electrical and thermal conductivity, properties that are often the very reason ultra-pure copper is specified in the first place.

Using our Fluidised Bed Reactor technology, we have successfully reduced oxygen levels in ultra-pure copper powders from greater than 100 ppm to below 40 ppm. Achieving this level of purification requires more than just a reductive atmosphere, it demands precise thermal control, carefully engineered gas chemistry, and stable, uniform fluidisation of highly cohesive fine powders.

Once again, the challenge lies not only in reducing oxygen, but in doing so without degrading powder flowability or surface condition. Ultra-pure copper powders, particularly after oxide removal, are extremely prone to cohesion. Our ability to manage these effects at scale is what allows recovered powders to return directly to demanding AM applications.

This capability further underscores the versatility of PSI’s fluidised bed technology, whether restoring high-value aerospace alloys like GRCop-42 or refining ultra-pure copper for the most performance-critical applications.

Recovering powder is only part of the story. For high-consequence applications, qualification is everything.

PSI’s GRCop-42 powder has not only met internal specifications for oxygen content, chemistry and flowability, it has gone a step further. Powder processed in our HERMIGA 120/250 V3I system has been qualified for use on Velo3D platforms through a third-party powder distributor.

This qualification confirms that the powder performs in one of the most demanding AM ecosystems in the aerospace sector. For customers operating Velo3D systems, this provides confidence that PSI-processed powders can be seamlessly introduced into production workflows without compromising build quality, repeatability or certification requirements.

Our capabilities extend well beyond copper alloys. Steel powders are among the most widely used AM materials and pose their own challenge due to the stability of chromium oxide. Despite its strong thermodynamic resistance to reduction, our investigations into 300M steel powders showed what is possible. Processing oxidised, out-of-spec material in our 235HT FBR reduced oxygen levels from 270 ppm to just 90 ppm, unlocking reuse where none was previously viable.

The impact is clear.

By extending powder life, we reduce waste, lower material costs, and help manufacturers maintain performance without compromise. From rocket launch to landing, our customers trust PSI to deliver refreshed powders that meet the demands of extreme environments.

Our FBR services go far beyond oxygen reduction. We offer engineered coatings, including ODS alloys, heat treatment and tailored powder modification, each designed to give metal powders a longer, more sustainable working life.

At PSI, we’re not just recycling powders.
We’re redefining what’s possible for Additive Manufacturing and helping build a greener future for high-performance materials.

Get in touch today to discuss how PSI can recover value from your AM powders.