Solution-Based Preparation of Metal Microspheres for Laser Powder Technologies: Formation Pathways, Conversion Barriers, and Validation Requirements
Eslam Hassan and Evgeny A. Trofimov published a review on October 25, 2026, in Powder Technology (impact factor 5.5), systematically assessing the feasibility of solution-derived metal microspheres as feedstock for laser powder bed fusion (LPBF) and directed energy deposition (DED). The article proposes a staged evidence framework that clearly distinguishes "particle formation evidence" from "powder processability evidence," noting that most current solution-based products remain at the stage of single-metal, hollow, porous, or nano-assembled structures and have not yet been validated under real powder processing and laser treatment conditions.
The review covers routes including wet chemical reduction, emulsion-confined growth, spray solution combustion, and secondary conversion. Wet chemical reduction can yield micron-sized spherical metal particles under controlled surfactants, pH, and mixing parameters, but extending this to multi-component microspheres requires that particle formation be coupled synchronously with controlled nucleation, co-reduction behavior, compositional homogeneity, stabilizer removal, and the integrity of drying post-treatment. The core criterion of the article is whether the same powder batch, after recovery, drying, classification, and thermal post-treatment, still maintains particle size distribution, composition, phase state, surface cleanliness, and mechanical integrity—rather than spherical morphology itself. On this basis, the authors define staged validation requirements for claims of powder processability and laser response, covering flowability, spreadability, packing density, and, under actual laser processing, melting behavior, melt pool stability, and defect rates.
For the metal additive manufacturing supply chain, the value of this review lies in shifting the discourse framework of solution methods from "morphology demonstration" to "batch certification." Atomization remains the industrial benchmark; the real opportunity for solution routes lies in the degree of chemical design freedom at the precursor level, but mass balance control, residue management, reproducibility metrics, and laser response feedback constitute conversion barriers from the laboratory to feedstock suppliers.
Value for powder buyers: (1) When evaluating solution-method suppliers, require data on composition, phase state, and oxygen content for the same batch after recovery and classification, rather than morphology photos of as-formed particles; (2) Incorporate flowability, spreadability, and packing density into incoming material acceptance indicators to fill the powder-level evidence gap in most current solution-method reports; (3) For multi-component alloy powders, focus on verifying elemental loss and residues caused by preferential reduction, and require suppliers to provide batch-to-batch reproducibility metrics.
2026-10-26
National Standard for EHS Metal Material Use in Metal Additive Manufacturing Enters Approval Stage; Three Powder National Standards Including Electrode Induction Gas Atomization Powder Production General Rules Under Development
The project "Metal Additive Manufacturing — Environmental, Health and Safety — General Rules for the Use of Metal Materials" (Plan No. 20251145-T-604, modified adoption of ISO/ASTM 52931:2023) has entered the "under approval" status: under the jurisdiction of SAC/TC562 and led by China Machinery Productivity Promotion Center, with 22 organizations including Vilory, AVIMETAL, Xi'an Sailong, Hanbang Laser, Yatong New Materials, and Leizhu Technology participating in drafting, it systematically standardizes risk assessment, preventive protection, and waste management for metal powder additive manufacturing, and is planned to take effect 6 months after publication. Powder-related national standards under development in parallel: "Additive Manufacturing — Metal Powders — General Rules for Electrode Induction Gas Atomization Powder Production" (20255907-T-610, drafting), "Gold and Gold Alloy Powders for Additive Manufacturing" (20262477-T-469, drafting), and "Additive Manufacturing — Technical Specification for Laser Powder Bed Fusion Stainless Steel Parts" (20264082-T-604, drafting) — a national standard matrix for powder EHS and powder production processes is taking shape, which will raise the compliance threshold and product capability standards for powder suppliers.
2026-10-25
