Atomistic fracture in bcc iron revealed by active learning of Gaussian approximation potential

作     者：Lei Zhang Gábor Csányi Erik van der Giessen Francesco Maresca 

作者机构：Engineering and Technology Institute GroningenFaculty of Science and EngineeringUniversity of GroningenNijenborgh 49747 AG GroningenThe Netherlands Engineering LaboratoryUniversity of CambridgeCambridge CB21PZUK Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 49747 AG GroningenThe Netherlands 

出 版 物：《npj Computational Materials》 (计算材料学（英文）)

年 卷 期：2023年第9卷第1期

页      面：135-145页

核心收录：

学科分类：08[工学] 080102[工学-固体力学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：This work made use of the Dutch national e-infrastructure with the support of the SURF Cooperative using grant no.EINF-2393 and EINF-3104.We thank the Centre for Information Technology of the University of Groningen(UG)for their support and for providing access to the Peregrine high performance computing cluster.L.Z.would like to thank Predrag Andric for LAMMPS implementation of fracture simulation and Miguel Caro for the implementation of Turbo SOAP descriptor.F.M.acknowledges the support from the start-up grant from the Faculty of Science and Engineering at the University of Groningen 

主　　题：approximation potential apply 

摘      要：The prediction of atomistic fracture mechanisms in body-centred cubic(bcc)iron is essential for understanding its semi-brittle *** atomistic simulations of the crack-tip under mode-I loading based on empirical interatomic potentials yield contradicting predictions and artificial *** enable fracture prediction with quantum accuracy,we develop a Gaussian approximation potential(GAP)using an active learning strategy by extending a density functional theory(DFT)database of ferromagnetic bcc *** apply the active learning algorithm and obtain a Fe GAP model with a converged model uncertainty over a broad range of stress intensity factors(SIFs)and for four crack *** learning efficiency of the approach is analysed,and the predicted critical SIFs are compared with Griffith and Rice *** simulations reveal that cleavage along the original crack plane is the atomistic fracture mechanism for{100}and{110}crack planes at T=0 K,thus settling a long-standing *** work also highlights the need for a multiscale approach to predicting fracture and intrinsic ductility,whereby finite temperature,finite loading rate effects and pre-existing defects(e.g.,nanovoids,dislocations)should be taken explicitly into account.