# Full-size 3D-printed tungsten tiles endure 74 plasma pulses in DIII-D tokamak

- Published: 2026-11-06 15:40 UTC
- Section: Power & Energy › Nuclear & fusion
- Tags: 3D printed tungsten, DIII D National Fusion Facility, electron beam powder bed fusion, tokamak divertor, fusion materials
- URL: https://realtech.media/news/rt-312c05064dbff7f3718358a3_full_size_3d/

**Engineers from NC State, ORNL, and JEOL manufactured full-scale divertor tiles via electron-beam 3D printing and verified their stability under high heat flux.**

![Full-size 3D-printed tungsten tiles endure 74 plasma pulses in DIII-D tokamak](https://sgzwpqqelzmajkcubgkl.supabase.co/storage/v1/object/public/rt-media/2026/11/c7dfc46734363c28.jpg)
*engr.ncsu.edu*

A research collaboration involving North Carolina State University, Oak Ridge National Laboratory (ORNL), and JEOL Ltd. has fabricated full-size tungsten tiles and tested them in the DIII-D National Fusion Facility in San Diego, according to engr.ncsu.edu [1]. The additively manufactured divertor components endured 74 direct plasma discharges with significant heat and particle flux without structural failure [1]. The hardware transition from program invitation to installation in the tokamak took approximately eight months [1].

## Powder bed fusion above ductile-to-brittle transition

Tungsten possesses the highest melting point of any metal at 3,422 °C and a density of 19.3 grams per cubic centimeter, making it the primary material candidate for divertor armor in tokamaks such as ITER [1]. However, conventional machining and casting remain difficult due to its ductile-to-brittle transition temperature, which falls between 200 °C and 600 °C, causing crack formation during laser-based printing processes [1]. To resolve thermal stress fractures, the team utilized electron-beam powder bed fusion (EB-PBF) inside a vacuum chamber [1]. The rapid scanning capabilities of the electron beam maintained the surrounding powder bed at temperatures above 1,400 °C throughout fabrication, keeping the metal well above its brittle range and yielding dense, crack-free components [1].

## Fabrication and in-vessel testing

JEOL engineered and printed the full-scale tiles on a large-format EB-PBF system in Japan, ORNL provided fusion materials expertise and funding, and NC State directed final machining, tight-tolerance finishing, and material characterization [1]. The divertor tiles are designed to operate in tokamak exhaust zones where steady-state heat loads reach 10 to 20 megawatts per square meter [1]. The campaign follows earlier Divertor Materials Evaluation System (DiMES) tests at DIII-D, where printed tungsten specimens handled heat fluxes approaching 20 megawatts per square meter, with peak pulses exceeding 35 megawatts per square meter, confirming baseline performance prior to full-tile deployment [1].

## Sources

1. [engr.ncsu.edu](https://engr.ncsu.edu/news/2026/10/26/nc-state-and-oak-ridge-3d-print-tungsten-tiles-for-use-in-fusion-facility/)
2. [Interesting Engineering](https://interestingengineering.com/energy/tungsten-plasma-blasts-in-us-fusion-reactor)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-312c05064dbff7f3718358a3_full_size_3d/