There are several methods to make metal 3D printing powder:
1.Mechanical Pulverization
Solid metal mechanical crushing method is an independent powder making method and can be used as a complementary process to some powder making methods. Relying on the role of crushing, smashing and grinding, the bulk of the metal, alloy or compound crushed into powder. The final degree of crushing can be divided into two categories: coarse crushing and fine crushing.
To further reduce or increase the size of the powder, alloying of the powder can select mechanical grinding
Applicable materials: Fe, Al, pure Ti powder and Fe-based alloys
2.Atomization Method
Atomization is a process in which liquid metals and alloys are broken directly into fine droplets that solidify quickly to form a powder. A high-velocity air or water stream is both the driving force and the coolant for the broken metal liquid stream. Any material that can form a liquid can essentially be atomized.
For low melting point metal powder, the granulation process is to let the molten metal through a small hole or screen automatically into the air or water, condensing to get metal powder, this method of making powder particle size coarse;.
Another method of preparing fine powder: water atomization or gas atomization method; centrifugal atomization method; and supersonic pulse inert gas atomization method. Take titanium alloy powder as an example, the titanium alloy powder is melted and atomized into fine droplets by high purity argon gas airflow, which falls under the action of gravity through the inert airflow, and the process of solidifying the fine particles into powder under its cooling.
At present, there are more applications of vacuum atomization method and inert gas atomization method (especially suitable for the preparation of active metal powder).
Applicable materials: Fe, Cu, refractory metals, stainless steel, Ti alloy, etc.
3.Reduction Method
The reduction is a method to produce metal powder by reducing metal oxides and salts with a reducing agent, where the reducing agent can be in solid, gaseous, or liquid form. Including carbon reduction method, gas reduction method, hydrogen reduction method, metal thermal reduction, the
Suitable materials: Fe, W, Ta, Zr as representatives of rare metals and refractory metal powders
4.Chemical Vapor Deposition (CVD)
Chemical vapor deposition using metal vapor condensation with a vapor phase reductant. These materials are characterized by a low melting point and a high volatility.
5.Electrolytic Method
A method of depositing powder from the cathode of an electrolytic cell under certain conditions. The electrolysis method is second only to the reduction method in terms of frequency of use. Although the manufacturing cost is high, the preparation purity is also high, and it has a similar purification effect on metal powder.
Principle: Chemical electrolysis
Applicable materials: Fe, Cu, Ni, Ti, and other metal powders, and intermetallic compounds.
6.Rotating Electrode Com-minuting Process
Currently the largest production scale and the most representative high-temperature alloy powder preparation method: plasma rotating electrode powder making method (i.e. PREP method), which prepares powder with good shape (round spherical), less porous powder and low oxygen content. This method is more costly and generally suitable for aerospace and biomedical fields.
Principle: The plasma gun is used to generate plasma flow in the sealed atomization chamber to melt the end of the high-speed rotating alloy bar material motor, and the liquid metal is atomized into very small droplets under the action of centrifugal force at the initial stage of the fly shot and cooled in the inert gas.
Applicable materials: Ni-based and other refractory metals, Ti and other active metals.
7.Spheroidizing Method
Spheroidization method mainly has: RF plasma spheroidization, laser plasma spheroidization and other heat sources of spheroidization
Principle: Take plasma spheroidization as an example: irregularly shaped titanium powder particles mixed with inert gas are added to the plasma torch, which is rapidly heated and melted by the plasma torch, and the molten particles form droplets with high sphericity under the action of surface tension, and spherical powder is obtained by rapid cooling in a very short time.
Applicable materials: mainly used for the secondary processing of irregular metal powder.
Frequently Asked Questions (FAQ)
1) Which powder-making method yields the most spherical particles for LPBF?
- PREP (plasma rotating electrode) and gas atomization (VIGA/EIGA) typically deliver highly spherical powders with low satellite content, ideal for powder bed fusion.
2) When should I choose water atomization over gas atomization?
- Water atomization is cost-effective for steels and produces finer powders, but with higher oxygen and irregular shapes. Choose GA for reactive alloys (Ti, Ni superalloys) and AM applications needing high flowability and low O/N.
3) Can mechanical pulverization produce AM-grade powders?
- Rarely. It’s useful for coarse or irregular feedstock and for secondary size adjustment, but usually requires downstream spheroidization (e.g., RF plasma) to reach AM-grade flow and morphology.
4) How do I minimize oxygen pickup during powder making and handling?
- Use inert atmospheres (argon), vacuum melting/atomization (VPA/VIGA/EIGA), dry rooms (<10% RH), sealed containers, and closed-loop powder handling per ISO/ASTM 52907 practices.
5) What QC tests are essential before qualifying a batch for AM?
- Particle size distribution (laser diffraction), morphology (SEM), flowability (Hall/Carney), apparent/tap density (ASTM B212/B703), chemistry O/N/H (ASTM E1019), and contamination/inclusions checks. Optional: CT of built coupons and microstructure.
2025 Industry Trends for the Best Methods of Metal 3D Printing Powder Making
- Hybrid routes: Water-atomized steels upgraded via RF plasma spheroidization to AM-grade flow at lower total cost.
- Clean melt expansion: EIGA/VPA capacity grows for Ti and Ni alloys, lowering oxygen baselines and stabilizing supply.
- Inline QA: Real-time optical/AI inspection at cyclones to control satellites and hollow particles; digital material passports standardize traceability.
- Sustainability: Argon recovery and powder circularity (reconditioning + reuse) reduce gas consumption 25–40% and extend reuse cycles to 8–12.
- Application-driven PSD: Narrow PSD tailoring for Binder Jetting sintering windows and DED deposition stability.
2025 Powder-Making KPI Snapshot
| Metric | 2023 Baseline | 2025 Status | Notes/Source |
|---|---|---|---|
| AM-grade O content (Ti-6Al-4V, wt%) | 0.07–0.12 | 0.05–0.10 | Improved VPA/EIGA and inert loops; ISO/ASTM 52907 |
| Sphericity (aspect ratio) GA/PREP | 0.92–0.96 | 0.94–0.98 | Better atomizer nozzles, plasma tuning; OEM datasheets |
| Hall flow (s/50 g, GA steels/Ni) | 16–22 | 15–19 | Satellite reduction via AI process control; ASTM B213 |
| Reuse cycles (AM, pre-blend) | 3–6 | 6–10 | Closed-loop handling; ASTM AM CoE |
| Argon use per kg powder (GA) | — | −25–40% | Argon reclamation; plant case studies |
| Share of hybrid WA+plasma for AM steels | low | rising | Cost/flow trade-off; industry reports |
Key references:
- ISO/ASTM 52907:2023 (metal powder characterization) https://www.iso.org/standard/78974.html
- ASTM B212/B213/B703, ASTM E1019 (density, flow, O/N/H) https://www.astm.org/
- NIST AM-Bench datasets https://www.nist.gov/ambench
- Wohlers Report 2025 market insights https://wohlersassociates.com/
Latest Research Cases
Case Study 1: RF Plasma Spheroidization Upgrades Water-Atomized 17-4PH for Binder Jetting (2025)
Background: A Tier-1 automotive supplier needed AM-grade flow without full GA costs for high-volume Binder Jetting.
Solution: Applied RF plasma spheroidization to WA 17-4PH, tightened PSD via classification, and optimized debind/sinter windows.
Results: Hausner ratio improved from 1.38→1.27; Hall flow from no-flow to 17.2 s/50 g; dimensional shrink variation cut by 35%; tensile properties met ASTM A564 equivalents after aging; per-kg powder cost 12–18% below GA alternative.
Case Study 2: EIGA Ti-6Al-4V Powder Reduces Oxygen Variability in Multi-Laser LPBF (2024)
Background: Aerospace producer saw fatigue scatter linked to oxygen drift in GA Ti powders across reuse cycles.
Solution: Switched to EIGA feedstock (PSD 20–45 μm), implemented closed-loop inert handling and AI melt pool monitoring; standardized HIP.
Results: O stabilized at 0.06–0.08 wt% across 8 reuse cycles; CT-detected lack-of-fusion rate reduced by 40%; HCF median life +22%; first-pass yield +16%.
Expert Opinions
- Dr. John Slotwinski, Materials Research Engineer, NIST
Key viewpoint: “For AM, the powder-making route is only half the story—consistent characterization (PSD, flow, O/N/H) per ISO/ASTM 52907 determines lot-to-lot reliability.” Source: NIST AM workshops https://www.nist.gov/ - Prof. Ian Gibson, Professor of Additive Manufacturing, University of Twente
Key viewpoint: “PREP and EIGA remain the gold standard for reactive alloys, but hybrid WA + plasma routes are closing the gap for steels where cost and throughput matter.” Source: AM conference proceedings https://www.utwente.nl/ - Dr. Anushree Chatterjee, Director, ASTM International AM Center of Excellence
Key viewpoint: “Digital material passports tied to standardized test data are accelerating powder qualification across platforms in 2025.” Source: ASTM AM CoE https://amcoe.astm.org/
Practical Tools/Resources
- ISO/ASTM 52907 (powder characterization)
https://www.iso.org/standard/78974.html - ASTM B212/B213/B703, E1019 (density, flow, tap density, O/N/H)
https://www.astm.org/ - NIST AM-Bench datasets and validation problems
https://www.nist.gov/ambench - Senvol Database: Compare machines/materials for AM powder routes
https://senvol.com/database - HSE ATEX/DSEAR: Powder handling and explosion safety
https://www.hse.gov.uk/fireandexplosion/atex.htm - Open-source/engineering tools: Thermo-Calc (CALPHAD), pySLM (scan path optimization), AdditiveFOAM (thermal/porosity simulation), ImageJ (particle morphology analysis)
Last updated: 2025-08-27
Changelog: Added 5 FAQs, 2025 trends with KPI table and sources, two recent case studies, expert viewpoints, and a curated tools/resources list aligned to ISO/ASTM best practices.
Next review date & triggers: 2026-03-31 or earlier if ISO/ASTM standards update, major atomizer capacity changes, or new safety directives affecting powder handling.
