Laser additive manufacturing technology is a manufacturing method that uses laser as the heat source and uses the high-energy beam focusing effect of laser to quickly melt metal powder.
Due to the high energy density of laser, it can realize the manufacturing of difficult-to-machine metals, such as titanium alloys and high-temperature alloys used in aerospace, etc. Laser additive manufacturing technology also has the advantage of not being limited by the structure of the parts, which can be used for the processing and manufacturing of complex structures, difficult processing and thin-walled parts.
At present, laser additive manufacturing technology has been applied to materials covering titanium alloys, high-temperature alloys, iron-based alloys, aluminum alloys, refractory alloys, amorphous alloys, ceramics and gradient materials, etc. It has significant advantages in the manufacture of high-performance complex components in the aerospace field and porous complex structures in the biomanufacturing field.
Additive manufacturing technology with laser as the heat source is mainly divided into laser deposition process based on powder feeding and laser selected area melting technology based on powder spreading.
Due to the different names of the units, the powder feeding-based laser melting deposition technology is also known as directed energy deposition, DED, laser solid forming, LSF, direct metal deposition, DMD, laser melting deposition, LMD, etc. Regardless of the name, the principle is to use the basic principle of rapid prototyping, using metal powder as the raw material, using a high-energy laser as the energy source, in accordance with the predetermined processing path, the synchronization of the metal powder given to the layer by layer melting, rapid solidification and layer by layer deposition, so as to achieve the direct manufacturing of metal parts.
Typically, the laser metal forming system platform consists of a laser, CNC table, powder feed nozzle, high precision adjustable powder feeder and other auxiliary devices as shown in the figure below. The lasers available for the pattern preparation process are mainly divided into semiconductor continuous lasers, fiber continuous lasers, CO2 continuous lasers and YAG:Nd pulsed lasers according to the beam pattern. According to the placement of nozzles, mainly divided into coaxial powder feeding nozzle group and lateral powder feeding nozzle.
Laser selective melting technology uses high brightness laser to directly melt metal powder material without binder, and 3D models are directly formed into any complex structural parts with comparable performance to forgings, and the parts only need surface finishing to be used. The main laser additive technologies include Selective Laser Melting (SLM), powder bed deposition process, etc.
The basic principle of laser zone melting is that the laser beam is scanned according to a pre-planned path to melt the pre-laid metal powder; after completing a level of scanning, the working chamber drops a layer in height and the powder layer re-laid a layer of powder, and so on repeatedly, layer by layer, until the required metal parts are manufactured, the whole process is in a vacuum environment, which can effectively avoid the influence of harmful impurities in the air.
The laser selective melting process can be directly made into end metal products, eliminating the intermediate transition. The prepared parts have high dimensional accuracy and good surface roughness (Ra 10~30μm) which is suitable for various complex shapes of workpieces, especially for complex workpieces with complex internal shaped structures. It cannot be manufactured by traditional methods; suitable for single and small batch complex structural parts without mold, rapid The machine is suitable for single-piece and low-volume complex structural parts without mold and rapid response manufacturing.
Additional FAQs: Laser Additive Manufacturing Technology
1) What are the main differences between Laser Powder Bed Fusion (LPBF/SLM) and Directed Energy Deposition (DED)?
- LPBF uses a powder bed and fine lasers to achieve high resolution and surface finish; best for complex, small-to-medium parts. DED feeds powder (or wire) into a laser melt pool; excels at larger parts, repairs, feature addition, and graded materials with higher deposition rates.
2) Which lasers are most common and how do they affect build quality?
- Fiber lasers (1070 nm) dominate for LPBF due to beam quality (M² ~1.1–1.5) and efficiency; high-power multimode fiber lasers (1–2 kW+) are common for DED. Shorter wavelengths (green, 515–532 nm) increasingly used for reflective metals like copper and precious alloys to improve absorptivity and reduce spatter.
3) How should powder specifications be chosen for laser additive manufacturing technology?
- Prefer spherical, gas/plasma-atomized powders with tight PSD: LPBF typically 15–45 µm; DED 45–150 µm. Control oxygen/nitrogen (e.g., Ti O ≤ 0.15–0.20 wt%, Al N ≤ 0.02 wt%), low satellites, high flowability, and consistent apparent/tap density to ensure repeatable melt behavior.
4) What post-processing is usually required to meet end-use properties?
- Stress relief and/or solution/aging heat treatments per alloy (e.g., IN718: solution + two-step age), Hot Isostatic Pressing (HIP) for defect closure, machining of interfaces, and surface finishing (blasting, chemical/electropolishing). NDT (CT, dye penetrant) is common for critical parts.
5) How do I minimize defects like porosity and lack-of-fusion?
- Calibrate volumetric energy density (ED = P/(v·h·t)), maintain dry/inert environments (O2 < 1000 ppm LPBF), optimize scan strategies (stripe/island, contour passes), ensure uniform powder spreading, and monitor recoater/optics health. For DED, maintain stable powder flow and coaxiality.
2025 Industry Trends: Laser Additive Manufacturing Technology
- Multi-laser LPBF mainstream: 8–12 laser systems become common, improving throughput 1.5–2.5× with advanced scan partitioning and interference mitigation.
- Green/blue laser adoption grows for copper, precious metals, and electronics heat spreaders, improving density and conductivity.
- Qualification momentum: More AMS/ASTM material allowables and OEM process specs for AlSi10Mg, Sc-modified Al, CuCrZr, IN718/625, and maraging steels.
- Closed-loop control: In-situ photodiodes, coaxial cameras, pyrometry, and melt-pool analytics enable adaptive parameter tuning and traceable quality records.
- Sustainability: Powder recycling programs and inert gas recirculation reduce consumables cost and footprint; recycled polymer and metal blends expand where certification allows.
2025 Snapshot: Performance, Cost, Adoption (Indicative)
| Metric | LPBF (2023) | LPBF (2025 YTD) | DED (2023) | DED (2025 YTD) | Notes |
|---|---|---|---|---|---|
| Typical build rate (Ti-6Al-4V) | 20–40 cm³/h per laser | 30–55 cm³/h per laser | 50–150 cm³/h | 80–220 cm³/h | Multi-laser + path optimization |
| Feature size (min wall) | 150–300 µm | 120–250 µm | 800–1500 µm | 600–1200 µm | Optics + scan tuning |
| As-built density (optimized) | 99.5–99.9% | 99.7–99.95% | 98.5–99.5% | 99.0–99.6% | Process window tightening |
| System price (new) | $400k–$1.2M | $450k–$1.5M | $500k–$2.5M | $600k–$3.0M | Larger platforms lift cap |
| Qualified alloys (commercial) | ~45–50 | ~60+ | ~20–25 | ~30+ | New Al, Cu, tool steels |
| Gas/O2 spec (LPBF chamber) | <1000 ppm | <500 ppm typical | N/A | N/A | Better gas management |
Sources:
- ASTM/ISO AM standards updates: https://www.astm.org, https://www.iso.org
- OEM technical notes (EOS, SLM Solutions, Trumpf, Renishaw, DMG MORI)
- NIST AM-Bench and melt pool monitoring research: https://www.nist.gov/ambench
- ContextAM/Wohlers market trackers (industry reports)
Latest Research Cases
Case Study 1: High-Conductivity Copper Heat Exchangers via Green-Laser LPBF (2025)
Background: An EV OEM targeted improved thermal management for power electronics.
Solution: Deployed 515 nm green-laser LPBF with CuCrZr powder (15–35 µm), optimized hatch and contour strategies; applied precipitation hardening post-build.
Results: 99.9% density, electrical conductivity 90–94% IACS, 23% lower junction temperatures vs. machined baseline, cycle time reduced 28% using dual-laser toolpaths.
Case Study 2: Hybrid DED Repair of IN718 Turbine Seals (2024)
Background: An MRO provider sought life extension for worn seal segments.
Solution: Used high-power fiber-laser DED with argon shielding and IN718 powder (53–106 µm); implemented inline coaxial monitoring and closed-loop powder flow control; post H900 aging.
Results: Dimensional restoration within ±0.15 mm, repaired parts passed fluorescent penetrant and CT; low-cycle fatigue life improved 18% over prior weld-repair method, cost per repair down 22%.
Expert Opinions
- Dr. Todd Palmer, Professor of Engineering Science and Mechanics, Penn State
- “Beam shaping and real-time control are closing the gap between as-built and wrought properties, especially for reflective alloys in laser additive manufacturing technology.”
- Dr. Ellen Cerreta, Division Leader, Materials Science and Technology, Los Alamos National Laboratory
- “Qualification hinges on microstructure control—laser scan strategies that stabilize grain structure and defect populations are proving as important as alloy chemistry.”
- Stefan Zeidler, Head of AM Solutions, TRUMPF
- “In 2025, productivity gains come from smarter multi-laser coordination and automated powder/gas management as much as from raw laser power.”
Practical Tools and Resources
- ISO/ASTM 52900 (terminology), 52907 (metal powder specs), 52904 (LPBF process), 52910 (design guidelines). https://www.iso.org
- ASTM F2924 (Ti-6Al-4V), F3055 (IN718), A1085/AMS specs for AM alloys. https://www.astm.org
- NIST resources on in-situ sensing and qualification for LPBF/DED. https://www.nist.gov/ambench
- OEM application libraries: EOS, SLM Solutions, Renishaw, Trumpf, DMG MORI (process parameters, case studies)
- Senvol Database for machine–material–process mapping. https://senvol.com
- OSHA/NIOSH guidance on laser safety, metal powders, and ventilation. https://www.osha.gov, https://www.cdc.gov/niosh
- MatWeb and Granta EduPack for material datasheets and comparisons. https://www.matweb.com
Last updated: 2025-08-25
Changelog: Added 5 FAQs specific to LPBF/DED; included 2025 trend table with performance/cost metrics; provided two recent case studies; compiled expert opinions; curated tools/resources with standards and databases
Next review date & triggers: 2026-02-01 or earlier if major LPBF/DED standard updates publish, multi-laser coordination breakthroughs are announced, or reflective metal (Cu/Ag/Au) process windows materially change
