Irradiation of W and K-Doped W Laminates without or with Cu, V, Ti Interlayers under a Pulsed 6 MeV Electron Beam.

D Ticoș,M L Mitu,C M Ticoș,M Dumitru,M Galaţanu,N Udrea,A Scurtu,A Galaţanu

doi:10.3390/ma15030956

Abstract

Small multilayered laminated samples consisting of stacks of W (or K-doped W) foils without an interlayer or with interlayers from Cu, V, and Ti were exposed to a pulsed electron beam with an energy of 6 MeV in several irradiation sessions. All samples maintained their macroscopic integrity, suggesting that the W-metal laminate concept is compatible with high heat flux applications. The surface of the samples was analyzed using a scanning electron microscope (SEM) before and after each irradiation session. The experimental results indicate that electron beam irradiation induces obvious modifications on the surface of the samples. Morphological changes such as the appearance of nanodroplets, nanostructures, and melting and cracking, depending on the sample type and the electron beam fluence, are observed. The irradiation is carried out in a vacuum at a pressure of 2 to 4 × 10−2 torr, without active cooling for the samples. The structures observed on the surface of the samples are likely due to electron beam heating and vaporization followed by vapor condensation in the volume adjacent to the surface.

Highlights

The nuclear fusion produced in magnetically confined plasmas stands out as the most promising green candidate for future energy generation [1]
The irradiation of laminates made of alternating layers of W, Cu, V, Ti and K-doped
The K-doped W laminate and a laminated sample made of pure W layers were exposed to a single 10-min irradiation session

Summary

Introduction

The nuclear fusion produced in magnetically confined plasmas stands out as the most promising green candidate for future energy generation [1]. The selected ITER plasmafacing materials have been tested at different facilities that recreate some of the conditions attained in fusion machines [1,2]. These facilities use powerful plasma guns or linear plasma devices to produce high-density plasma [3,4,5,6,7,8,9], electron beams [10,11,12,13,14], and ion beams (mostly H+ and He+) [8,12,15]. The investigation of the erosion as induced by deuterium ions in beryllium, tungsten, and carbon shows that the sputtering yield for tungsten is the lowest, being almost one order of magnitude lower than that of carbon for energy ranges between 100 and 10 keV [17,18]

Methods

Results

Discussion

Conclusion