TY - JOUR

T1 - Helium-induced swelling and mechanical property degradation in ultrafine-grained W and W-Cu nanocomposites for fusion applications

AU - Wurmshuber, Michael

AU - Balooch, Mehdi

AU - Huang, Xi

AU - Hosemann, Peter

AU - Kiener, Daniel

N1 - Funding Information: The authors acknowledge funding by the European Research Council under Grant No. 771146 (TOUGHIT). Additional financial support was provided by the Austrian Marshall Plan Foundation. The authors acknowledge further support from NSF DMR Award No. 1807822. The authors thank Dr. Michael Burtscher for providing TEM images of the W-Cu nanocomposite and Simon Doppermann for help with sample fabrication.

PY - 2022/5

Y1 - 2022/5

N2 - Besides high dose radiation and extreme thermal loads, a major concern for materials deployed in novel nuclear fusion reactors is the formation and growth of helium bubbles. This work investigates the swelling and mechanical property degradation after helium implantation of ultrafine-grained W and nanocrystalline W-Cu, possible candidates for divertor and heat-sink materials in fusion reactors, respectively. It is found that ultrafine-grained W and single crystalline W experience similar volumetric swelling after helium implantation but show different blistering behavior. The W-Cu nanocomposite, however, shows a reduced swelling compared to a coarse-grained composite due to the effective annihilation of radiation-induced vacancies through interfaces. Furthermore, the helium-filled cavity structures lead to considerable softening of the composite.

AB - Besides high dose radiation and extreme thermal loads, a major concern for materials deployed in novel nuclear fusion reactors is the formation and growth of helium bubbles. This work investigates the swelling and mechanical property degradation after helium implantation of ultrafine-grained W and nanocrystalline W-Cu, possible candidates for divertor and heat-sink materials in fusion reactors, respectively. It is found that ultrafine-grained W and single crystalline W experience similar volumetric swelling after helium implantation but show different blistering behavior. The W-Cu nanocomposite, however, shows a reduced swelling compared to a coarse-grained composite due to the effective annihilation of radiation-induced vacancies through interfaces. Furthermore, the helium-filled cavity structures lead to considerable softening of the composite.

UR - http://www.scopus.com/inward/record.url?scp=85125543832&partnerID=8YFLogxK

U2 - 10.1016/j.scriptamat.2022.114641

DO - 10.1016/j.scriptamat.2022.114641

M3 - Article

VL - 213.2022

JO - Scripta materialia

JF - Scripta materialia

SN - 1359-6462

IS - May

M1 - 114641

ER -