Generation of vacancies in high-speed plastic deformation

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 350; no. 1; pp. 216 - 219
• Main Author: Fujita, Francisco Eiichi
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 15-06-2003; Elsevier
• Subjects: Cavitations and vacancies; Condensed matter: structure, mechanical and thermal properties; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Fluid dynamics and solids; High-speed deformation; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Physics; Vacancy production; Vacancy production; Cavitations and vacancies; High-speed deformation; Fluid dynamics and solids; Streamlines; Turbulence; Plastic flow; Theoretical study; Dynamic properties; Vacancy cluster; High speed; Plasticity; Modelling; Defect formation; Flow stress
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/S0921-5093(02)00690-1

In a recent experiment, crystalline metals were subjected to high-speed plastic deformation, and subsequently a number of vacancy clusters were observed without any trace of dislocations. In an effort to explain this result, in the present study fluid-like behavior of solid in ultra-high-speed deformation is considered, and the possibility of spontaneous generation of vacancies analogous to cavitation in high-speed fluid flow is discussed. Similar to a large velocity gradient that induces turbulence in a high-speed fluid flow, large shear stress induced in a solid material during the course of high-speed deformation may generate vacancies instead of dislocations, if the dislocations cannot follow the deformation speed. In this paper, similarities between dislocation in solid and vortex in a fluid discussed, along with similarities between vacancy in a solid and cavitation in fluid, and a mechanism of vacancy production under high-speed plastic deformation of crystalline materials is proposed.