Dislocation Density-Based Constitutive Model for the Mechanical Behavior of Irradiated Cu.

Arsenlis, A. ; Wirth, B. D. ; Rhee, M.

Technical Information Center Oak Ridge Tennessee

关键词: Copper alloys;    Mechanical properties;    Defects;    Dislocations;    Ductility;   

RP-ID  :  DE200415007747

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Performance degradation of structural steels in nuclear environments results from the development of a high number density of nanometer scale defects. The defects observed in copper-based alloys are composed of vacancy clusters in the form of stacking fault tetrahedra and/or prismatic dislocation loops, which impede dislocation glide and are evidenced in macroscopic uniaxial stress-strain curves as increased yield strengths, decreased total strain to failure, decreased work hardening and the appearance of a distinct upper yield point above a critical defect concentration (neutron dose). In this paper, we describe the development of an internal state variable model for the mechanical behavior of materials subject to these environments. This model has been developed within an information-passing multiscale materials modeling framework, in which molecular dynamics simulations of dislocation--radiation defect interactions, inform the final coarse-grained continuum model.