High geometric complexity at high accuracy delays the construction of new stellarators and the related research. Thus, exploring whether additive manufacturing (AM) might provide advantages to the fabrication and design philosophy of stellarators appears valuable. Three coil frame supports were designed, produced by three AM techniques (SLA, FDM, and PolyJet) and measured by a Coordinate Measuring Machine. For FDM (similar to SLA), average of ±0.17% mean deviation was obtained and 68% of the points (one sigma) deviate less than ±0.28%. Three assays were performed for modular stellarator vacuum vessels: 1) a thin copper liner attached to a resin shell cast in an AM mold; 2) a thin electroformed liner for a test vacuum vessel; and 3) electrodeposited coating on an AM shell. The assays showed alternative 3) the simplest and fastest. The results from such studies and assays are reported and integrated with the previous results. Low stiffness and strength of AM plastics was previously tackled with fiber-reinforced resin cast in AM hollow structures (3Dformwork technique). Thus, AM, particularly combined with other fabrication methods, proved to be appropriate for the production of certain unpretentious small- and middle-size stellarators.
Bibliographical noteFunding Information:
Manuscript received June 3, 2017; revised October 3, 2017; accepted December 5, 2017. Date of publication January 23, 2018; date of current version May 8, 2018. This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness and the Fondo Europeo de Desarrollo Regional through this Project “Study of AM for the application to high performance fusion devices of stellarator type” under Contract ENE2015-64981-R (MINECO/FEDER, EU). The review of this paper was arranged by Senior Editor E. Surrey. (Corresponding author: Vicente Queral.) The authors are with the National Fusion Laboratory, Centro de Investiga-ciones Energéticas, Medioambientales y Tecnológicas, 28040 Madrid, Spain (e-mail: firstname.lastname@example.org).
- Additive manufacturing (AM)
- dimensional accuracy
- vacuum vessel