Detail Observation of Giant Diffusivity Along Dislocation Cores   Oleh:  Legros, Marc ; Dehm, Gerhard ; Arzt, Eduard ; Balk, T. John Jenis: Article from Bulletin/Magazine Dalam koleksi: SCIENCE (keterangan: ada di Proquest) vol. 319 no. 5870 (Mar. 2008), page 1646-1648. Topik: Giant Diffusivity Ketersediaan Perpustakaan FK Nomor Panggil: S01.K.2008.03 Non-tandon: 1 (dapat dipinjam: 0) Tandon: tidak ada     Lihat Detail Induk Isi artikel Diffusion of atoms in a crystalline lattice is a thermally activated process that can be strongly accelerated by defects such as grain boundaries or dislocations. When carried by dislocations, this elemental mechanism is known as "pipe diffusion." Pipe diffusion has been used to explain abnormal diffusion, Cottrell atmospheres, and dislocation-precipitate interactions during creep, although this rests more on conjecture than on direct demonstration. The motion of dislocations between silicon nanoprecipitates in an aluminum thin film was recently observed and controlled via in situ transmission electron microscopy. We observed the pipe diffusion phenomenon and measured the diffusivity along a single dislocation line. It is found that dislocations accelerate the diffusion of impurities by almost three orders of magnitude as compared with bulk diffusion. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Kembali

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