Relaxed Configuration of a Row of Punched Prismatic Disix)cation Loops

نویسندگان

  • David C. Dunand
  • Andreas Mortensen
چکیده

Punched rows of coaxial, circular prismatic dislocation loops can be produced in a crystal by several mechanisms: growth of a second phase in a ductile matrix (1), growth of gas bubbles in irradiated metals (2), mechanical indentation (3), elastic constant mismatch strains induced by isostatic pressurization (4) or by shear (5) and strain mismatch due to a difference of coefficient of thermal expansion and temperature change (6,7). The loops within such a row are nucleated one by one at their source, from which they are repelled by following loops until an equilibrium configuration is reached where nucleation stops and all loops are at rest, unable to overcome lattice friction. The resulting loop spacings in the row are of interest since they govern the local dislocation density in, as welt as the size of, the resulting plastic zone.

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تاریخ انتشار 2003