Direct Energy Deposition Methods

A month ago, I shared a simulation video of the 𝐃𝐢𝐫𝐞𝐜𝐭𝐞𝐝 𝐄𝐧𝐞𝐫𝐠𝐲 𝐃𝐞𝐩𝐨𝐬𝐢𝐭𝐢𝐨𝐧 (𝐃𝐄𝐃) process of a titanium wire. Since then, we've added 𝐆𝐏𝐔 𝐬𝐮𝐩𝐩𝐨𝐫𝐭 to our simulation software, significantly reducing simulation time and enabling more complex and detailed studies. The following video demonstrates the deposition process of a titanium wire (1 mm radius) on a (4 x 4) cm² substrate across 𝐟𝐨𝐮𝐫 𝐥𝐚𝐲𝐞𝐫𝐬. The wire is melted using 𝐭𝐡𝐫𝐞𝐞 𝐆𝐚𝐮𝐬𝐬𝐢𝐚𝐧 𝐥𝐚𝐬𝐞𝐫 𝐛𝐞𝐚𝐦𝐬, each's power is individually controlled to maximize the deposition rate. The breakage of the liquid bridge connecting the wire and substrate can be observed during the deposition of the last track in the fourth layer. We employ a 𝐫𝐚𝐲 𝐭𝐫𝐚𝐜𝐢𝐧𝐠 algorithm to model the laser-material interaction, where the total laser power is distributed among numerous rays. The laser energy absorbed by the material surface is computed based on ray intersections with the material surface, considering surface temperature, angle of incidence, and polarization. In the video, the upper section displays the temperature field, while the lower section shows the number of ray intersections with the material surface throughout the simulation. Simulated on a Ryzen 7950x3D and an RTX4070. The video is rendered using Blender. Get in touch with us at blank-simulations if you see potential application scenarios. #SPH #multiphysics #raytracing #additivemanufacturing 𝐌𝐞𝐭𝐡𝐨𝐝: - Smoothed Particle Hydrodynamics (SPH) - MPI-OpenMP parallelization - GPU-acceleration - Dynamic workload balancing - Adaptive particle refinement 𝐏𝐡𝐲𝐬𝐢𝐜𝐬: - Ray tracing to model laser-material interaction - Temperature-dependent material properties - Latent heat of fusion and crystallization - Evaporation and recoil pressure - Surface tension and wetting

If you are interested in bimetallic 3D printing, check out the most recent paper from our newly created Materials Development and Additive Manufacturing Group at NASA JPL. The paper, titled “Fe-Ni Alloys and Novel Bi-Metallic Magnetic Shields,” is published in the Journal of Magnetism and Magnetic Materials with lead author Samad Firdosy. In the paper, they present a novel approach to manufacturing monolithic bi-metallic shielding, utilizing our blown powder directed energy deposition printer. The research demonstrates that the bi-metallic shielding, composed of high saturation and high permeability alloys, leads to a significant increase in shield effectiveness (~9dB) when compared to a single alloy shield. The DED Fe-80Ni-5Mo alloy produced in this study has among the highest permeability and lowest coercivity of any AM soft magnetic alloy reported thus far. The DED process is proving very capable for manufacturing novel magnetic materials. It has been used to print monolithic magnetic alloys with tailored grain size, bimetallic magnetic shields, functionally graded alloys, magnetic amorphous metals, and metal matrix composites. Even though the DED can’t produce parts with the same complexity as powder bed fusion, the ability to create new materials that would be difficult or impossible to make otherwise gives this technique a wedge of applications. Combined with our subtractive manufacturing capabilities and our worldclass machinists, DED can be used to produce some exceptional parts, such as magnetic shielding for spacecraft, for example. #3dprinting https://lnkd.in/gKdmvh-X

In situ microstructure control during electric-arc directed energy deposition Our recent publication in the Virtual and Physical Prototyping (https://lnkd.in/gg42KXGJ ) journal is focused on understanding the in situ microstructure control during electric-arc directed energy deposition. Powder-based metal additive processes like powder bed fusion (PBF) and DED dominate the metal additive manufacturing (AM) industry. They produce structures layer by layer using laser or plasma beam energy sources to fuse powder particles in sealed build chambers, with layer thicknesses generally measuring between 3 and 30 μm. Intricate, high-resolution designs in various materials are standard, but deposition is painfully slow and volumetrically constrained. Wire-based Arc-DED directly addresses both of those fundamental limitations. In this newer approach, an electric arc provides heat to melt and deposit material layer by layer. Layer thicknesses for Arc-DED are consistently nearer to 3mm for significant rate and cost efficiencies. The approach leverages mature welding technology and automation for nearly unrestricted build envelopes. Greater layer thickness easily translates into accelerated build times, with each pass by Arc-DED depositing almost 100 times the material added in a single layer by PBF. Unfortunately, the high energy needed for these rates and thicknesses intensifies the heating and cooling cycles inherent to Arc-DED. This causes significant variations in microstructural and mechanical properties, limiting its use for advanced alloys. This study introduces a conformal top cooling method to regulate the chaotic thermal environment of Arc-DED deposition and produce as-deposited Inconel 718 (IN718) material equivalent to the solutionized condition. The concept is experimentally investigated using cold metal transfer (CMT) of IN718. The role of microstructural and phase uniformity during material production is discussed, material performance in as-deposited and heat-treated conditions is evaluated, processing-property relationships are investigated, and applicability to other materials is addressed. Results show a 45% reduction in process time due to improved thermal management, translating to as-processed microstructural uniformity. Homogeneity in grain growth, controlled phase development, and mechanical testing suggests an as-processed solutionizing effect, with minimized impact of specimen orientation after heat treatment. The full-text article can be accessed at - https://lnkd.in/g7gHsfGn Full citation – Lile Squires, Victor Champagne & Amit Bandyopadhyay (2025) In Situ microstructure control during electric-arc-directed energy deposition, Virtual and Physical Prototyping, 20:1, e2499929, DOI: 10.1080/17452759.2025.2499929 #additivemanufacturing #3dprinting #wsu #metallurgy #msecoug    

Directed Energy Deposition (DED) enables the combination of dissimilar materials in a single component, enhancing performance and functionality. A prime example is the integration of copper and Inconel. Copper, known for its excellent thermal and electrical conductivity, is ideal for heat dissipation, while Inconel, a high-temperature-resistant superalloy, provides strength and oxidation resistance. By leveraging #DED, manufacturers can create optimized hybrid components, such as high-performance heat exchangers or rocket engine nozzles, where copper efficiently conducts heat away, and Inconel ensures structural integrity under extreme conditions. This approach reduces material waste, improves performance, and extends component lifespan, making it a game-changer in aerospace, energy, and advanced manufacturing industries. At our Laser Center of Competence we have gained interesting experiences by working with multi-materials in the frame of Disco2030 #disco2030 https://lnkd.in/ejcGNCh4

In the Wire-Laser Directed Energy Deposition process, the specific energy supplied to the feed wire determines the mode of material transfer and process stability. This video demonstrates a high-fidelity simulation of single-layer single-track duplex stainless steel alloy deposition during the WLAM process, performed using AM PravaH scientific software. A 4500W Gaussian laser is used to melt the feed wire, which moves at 2 m/min. The high laser energy is sufficient to melt the wire, and a narrow transition link is formed, enabling the metal transfer through liquid bridge mode. The input laser power directly influences the maximum temperature of the melt pool. At such high laser inputs, vaporization effects are predominant, and gas entrapment within the molten alloy is visible. This will eventually promote pore formation and other internal defects in the final build part.   Creating favorable conditions for the pores to escape is crucial in reducing pore nucleation sites and internal porosity defects. Using AM PravaH, parameter optimization studies can be performed to ensure smooth material transfer, thus enhancing the part quality. #additivemanufacturing #simulation

EBAM - Electron Beam Additive Manufacturing I recently talked about WAAM (wire arc additive manufacturing). Today let’s talk about another DED (directed energy deposition) process: electron beam additive manufacturing aka EBAM. As you might guess, EBAM uses an electron beam to melt metal. A stream of electrons is created by heating a tungsten filament and then directed where desired by a magnetic field.   It is done in a vacuum so the electrons don’t collide with other atoms/molecules. The process fuses together layers of material to build it up into a complex structure. Somewhat confusingly, EBAM as a term can be used to refer to processes that use either powder or wire as the raw material (also called feedstock). And more confusingly, a bunch of different terms are used for the electron beam based powder processes including electron beam powder bed fusion (E-PBF), electron beam melting (EBM), selective electron beam melting (SEBM), and electron beam selective melting (EBSM). I have also seen the wire version of EBAM referred to as EB-FFF as in electron beam free form fabrication. And because FFF is often called FDM (fused deposition modeling) despite being trademarked by Stratasys, I have also seen wire based EBAM called EB-FDM. However, these names for the wire process seem less common. Regardless of which feedstock you are using or what you call it, each process comes with its own set of advantages and disadvantages. In manufacturing, there is no one perfect tool for everything so it understand when something is a good option. The benefits of both wire and powder EBAM include the ability to create complex shapes without tooling. This, like other AM processes, enables the ability to manufacture low volume components more easily such as for rapid prototyping, customization, tooling, or replacement parts. The drawbacks of both are that equipment is high cost relative to the deposition rate. Powder has more precision but has an improved deposition rate compared to laser beam powder bed fusion.  This precision makes it easier to make finer support structures that are easier to remove. It also works better with higher melting point metals or those that are highly reflective. Wire tends to have less dimensional accuracy but an improved deposition rate. Sciaky report up to 20 pounds an hour. It also has a wider material availability compared to powders and wire tends to be less costly for the same alloy than powder.  On the downside, most wire processes tend to be near net. They typically require post process machining which can add time and cost to the component manufacturing. This can be addressed by hybrid additive manufacturing but that is a topic for another day. What do you see as the most important benefit or drawback of these processes? #MetallurgyMonday #betterlatethannever  

Our latest research on metal additive manufacturing using laser-directed energy deposition (L-DED) has been published open access in Welding in the World. As a collaboration among LUT University’s laboratories LUT Laser Material Processing and Additive Manufacturing (LUT Laser), LUT Steel Structures, and LUT Welding Technology - LUT Hitsaustekniikka, Vesa Tepponen explored the use of 316LSi stainless steel with wire feeding as a viable solution for producing large-scale industrial metal components using additive manufacturing. The study investigates: • Mechanical performance and anisotropy • Microstructural evolution • Surface quality • Build-related challenges in wire-fed L-DED The findings help advance the industrial readiness of wire-based metal additive manufacturing across multiple sectors. Read the full article: https://lnkd.in/dPRjpFjr #additivemanufacturing #metalAM #directenergydeposition #metalAM