Youbin Kim, Jinwook Baek, Sunghwan Kim, Sangmin Kim, Seunghwa Ryu, Seokwoo Jeon & Seung Min Han
Scientific Reports 6, Article number: 24785 (2016)
Received: 19 October 2015
Accepted: 31 March 2016
Published online: 21 April 2016
Ultra high strength V-graphene nanolayers were developed for the first time that was demonstrated to have an excellent radiation tolerance as revealed by the He+ irradiation study. Radiation induced hardening, evaluated via nanopillar compressions before and after He+ irradiation, is significantly reduced with the inclusion of graphene layers; the flow stresses of V-graphene nanolayers with 110 nm repeat layer spacing showed an increase of 25% while pure V showed an increase of 88% after He+ dosage of 13.5 dpa. The molecular dynamics simulations confirmed that the graphene interface can spontaneously absorb the nearby crystalline defects that are produced from a collision cascade, thereby enhancing the lifetime of the V-graphene nanolayers via this self-healing effect. In addition, the impermeability of He gas through the graphene resulted in suppression of He bubble agglomerations that in turn reduced embrittlement. In-situ SEM compression also showed the ability of graphene to hinder crack propagation that suppressed the failure.