Additive Manufacturing Process Characterization and Powder Properties

Additive manufacturing relies on the precise deposition and consolidation of fine powders to produce complex three-dimensional parts with tailored properties. Central to process performance is the characterization of powder properties—such as particle size distribution, shape, surface texture, flowability and cohesion—and their influence on layer deposition, melt dynamics and final component integrity. Advanced diagnostics encompass in situ imaging, rheometry, shear testing and thermal monitoring, complemented by numerical simulations to capture particle-scale interactions during spreading and fusion. The interplay between powder morphology and process parameters governs layer uniformity, defect formation and mechanical performance. Recent efforts have focused on standardising measurement protocols, refining discrete element models to predict spreading behaviour and integrating high-resolution monitoring to close the loop between powder feedstock attributes and part quality. These developments underpin the optimisation of powder bed fusion, binder-jetting and other powder-based techniques, supporting broader adoption across aerospace, biomedical and energy applications.

Research from Nature Portfolio

High-speed X-ray imaging has revealed the evolution of powder cluster dynamics and repose angle during spreading, offering unprecedented insight into frictional interactions between particles and boundaries. This particle‐scale characterisation has enabled more accurate predictions of powder bed quality and informed the calibration of models used in powder‐bed fusion processes. In parallel, systematic evaluation of ten industrial metal powders by rotary shear testing and flow index analysis has highlighted the dependence of flowability on particle size distribution, surface energy and moisture uptake. Comparing multiple rheometers has underscored the need for harmonised protocols, while establishing correlations between static angle of repose and effective internal friction to guide feedstock selection and process parameter tuning.

Additive Manufacturing Process Characterization and Powder Properties publication trend

The graph below shows the total number of articles in additive manufacturing process characterization and powder properties across all publications each year (not limited to Nature Index journals).

Technical terms

Powder bed fusion (PBF): A family of AM techniques in which a heat source selectively fuses regions of a powder layer to build parts layer by layer.

Flowability: The ease with which powder particles move and rearrange under applied forces, often quantified by angle of repose or flow index measurements.

Spreadability: The ability of a powder to form a uniform, defect-free layer during recoating, influenced by cohesion, morphology and spreading tool design.

Discrete element method (DEM): A numerical simulation technique that models individual particles and their interactions to predict bulk powder behaviour during processing.

Angle of repose: The steepest angle at which a pile of powder remains stable, serving as an indirect measure of interparticle friction and cohesion.

References

1. Study on powder particle behavior in powder spreading with discrete element method and its critical implications for binder jetting additive manufacturing processes. Virtual and Physical Prototyping (2023).
2. Melt pool signatures of TiN nanoparticle dry-coated Co25Cr25Fe25Ni25 metal powder in laser-powder-bed-fusion. Materials & Design (2023).
3. Spreadability of powders for additive manufacturing: A critical review of metrics and characterisation methods. Particuology (2024).
4. Revealing particle-scale powder spreading dynamics in powder-bed-based additive manufacturing process by high-speed x-ray imaging. Scientific Reports (2018).
5. Characterization and flowability methods for metal powders. Scientific Reports (2020).