Details

Autor(en) / Beteiligte

• Wu, X L
• Zhu, Y T
• Wei, Y G
• Wei, Q

Titel

Strong strain hardening in nanocrystalline nickel

Ist Teil von

• Physical review letters, 2009-11, Vol.103 (20), p.205504-205504, Article 205504

Ort / Verlag

United States

Erscheinungsjahr

2009

Quelle

PROLA - Physical Review Online Archive

Beschreibungen/Notizen

• Low strain hardening has hitherto been considered an intrinsic behavior for most nanocrystalline (NC) metals, due to their perceived inability to accumulate dislocations. In this Letter, we show strong strain hardening in NC nickel with a grain size of approximately 20 nm under large plastic strains. Contrary to common belief, we have observed significant dislocation accumulation in the grain interior. This is enabled primarily by Lomer-Cottrell locks, which pin the lock-forming dislocations and obstruct dislocation motion. These observations may help with developing strong and ductile NC metals and alloys.