Direct Evidence of a Deformation Mechanism Crossover in Nanocrystalline Nickel

✍ Scribed by Z. Shan; S. X. Mao

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 276 KB
• Volume: 7
• Category: Article
• ISSN: 1438-1656
• DOI: 10.1002/adem.200500034

✦ Synopsis

Evidence for deformation mechanism crossover, i.e. from dislocation nucleation and motion to grain boundary mediated plasticity, has been sought for many years, but direct experimental confirmation remains elusive. By employing in situ dynamics dark field transmission electron microscope investigation on nanocrystalline nickel films with an average grain size of about 10 nm, the authors show conclusive experimental evidence that grain boundary plasticity has begin to dominate the deformation of as deposited Ni. The physical mechanism that governs the observed phenomenon is discussed.