materials-logo

Journal Browser

Journal Browser

Understanding and Further Development of Directed Energy Deposition Process

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Manufacturing Processes and Systems".

Deadline for manuscript submissions: 20 March 2027 | Viewed by 760

Editor


E-Mail Website
Guest Editor
Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 576-0047, Japan
Interests: thermal plasma; plasma diagnostics; computational fluid dynamics; arc welding; plasma cutting; electric contacts; arc lamp
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Directed energy deposition (DED) is a type of additive manufacturing in which material is melted using a heat source such as an arc or laser and then deposited layer by layer to fabricate three-dimensional products without joints. This process is suitable for fabricating complex shape structures and has many other advantages, such as a significant reduction in the amount of materials and labor required. Furthermore, it can also be applied for fabricating functionally graded materials. Accordingly, it has become one of the manufacturing processes attracting particular attention in recent years. In order to enhance the strength of the DED process, significant research to understand the process mechanisms on a scientific basis and develop advanced processes has been actively carried out all over the world. However, further work is still required in this field. The scope of this Special Issue focuses on the understanding and further development of the DED process. The topics of interest include, but are not limited to, the following:

  • Developments of advanced DED process;
  • Modeling and simulation of DED process;
  • Heat source properties;
  • Heat source–material interaction mechanisms;
  • Fluid mechanics and heat transfer in weld pools;
  • Solidification and microstructure formation mechanisms.

We would like to invite you to submit original research articles and reviews related to any topics mentioned above.

Dr. Shinichi Tashiro
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-anonymized peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • directed energy deposition
  • additive manufacturing
  • process mechanisms
  • heat source properties
  • heat source–material interaction
  • heat transfer
  • fluid mechanics
  • weld pool
  • microstructure
  • mechanical properties

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (2 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

18 pages, 5231 KB  
Article
External Magnetic Field-Assisted Porosity Reduction in Plasma Arc-Based Wire Arc Additive Manufacturing
by Shinichi Tashiro, Dang Khoi Le, Huy Le Phan, Quang Huy Duong, Kieu A. Duong Nguyen, Toshifumi Yuji, Bin Xu and Manabu Tanaka
Materials 2026, 19(16), 3477; https://doi.org/10.3390/ma19163477 - 17 Aug 2026
Abstract
This study proposed porosity reduction technology for Wire Arc Additive Manufacturing (WAAM) of aluminum alloys that employ a static transversal External Magnetic Field (EMF) to control cathode spot (CS) behavior for the first time, thereby facilitating bubble release, mainly by accelerating the removal [...] Read more.
This study proposed porosity reduction technology for Wire Arc Additive Manufacturing (WAAM) of aluminum alloys that employ a static transversal External Magnetic Field (EMF) to control cathode spot (CS) behavior for the first time, thereby facilitating bubble release, mainly by accelerating the removal of oxide layer. This paper reported effects of EMF strength (Magnetic Flux Density: MFD) on porosity reduction. The pore diameter distributions showed that the number of pores at MFDs of 2 mT and 3 mT decreased to approximately half of that at 0 mT and 1 mT for pore diameters less than 60 μm, indicating that applying EMF with MFD higher than 2 mT especially contributed to reducing the pore formation. The observation presented that the Electrode Negative (EN) arc effectively melted the wire, and the Electrode Positive (EP) arc cleaned the oxide layer on the rear weld pool surface by CSs with EMF. There were two types of bubble release behavior: a weak eruption outside the arc root (Type A), and a strong eruption inside the arc root (or CS) (Type B). Type B is considered to be more effective for porosity reduction, being caused by oxide removal by CS. One possible explanation for this is that the gas bubbles trapped beneath the oxide layer could be strongly drawn out through CS. Full article
Show Figures

Figure 1

14 pages, 3358 KB  
Article
Analysis of Al2O3 Single-Bead Deposition Behavior and Microstructure on a Ti-6Al-4V Substrate Using the Laser-Directed Energy Deposition (DED-LB) Process
by Tae-Hyeon Kim, Jin-Soo Lee, Sang-In Kim, Su-Han Bae, Changjong Kim and Se-Yun Kim
Materials 2026, 19(11), 2369; https://doi.org/10.3390/ma19112369 - 2 Jun 2026
Viewed by 341
Abstract
Al2O3 single beads were deposited on a Ti-6Al-4V (Ti64) substrate by laser-directed energy deposition (DED-LB) to establish baseline process conditions for ceramic protective layers and future Ti64/Al2O3 functionally graded materials (FGMs). These ceramic-containing surface layers are applicable [...] Read more.
Al2O3 single beads were deposited on a Ti-6Al-4V (Ti64) substrate by laser-directed energy deposition (DED-LB) to establish baseline process conditions for ceramic protective layers and future Ti64/Al2O3 functionally graded materials (FGMs). These ceramic-containing surface layers are applicable to titanium components requiring improved oxidation, wear, and thermal resistance in aerospace, automotive, and high-temperature structural applications. Laser power (300–700 W) and scan speed (300–700 mm/min) were varied, and bead geometry was quantified from cross-sectional observations; energy density and dilution ratio were calculated. Melt pool depth increased with higher power and lower speed, indicating increased heat input and substrate melting. Crack formation in the melt zone was more sensitive to laser power than to scan speed. In contrast, bead height showed a non-monotonic response to energy density, which may be associated with possible coupled effects such as recoil pressure-driven melt pool disturbance, powder scattering, and insufficient powder melting at high scan speeds. Dilution-based optimization identified 300 W laser power and 400 mm/min scan speed, with a powder feed rate of 3 g/min, as the most suitable condition within the investigated process window, giving the lowest practical dilution ratio of approximately 40.27%. SEM–EDS and XRD analyses were conducted to examine the interfacial microstructure and phase characteristics under the selected condition. Overall, this study provides fundamental process guidelines and mechanistic insight into bead formation, dilution behavior, and interface formation, supporting the future application of DED-LB-based ceramic protective or graded layers on Ti64 surfaces. Full article
Show Figures

Figure 1

Back to TopTop