Near-perfect elastoplasticity in pure nanocrystalline copper.
Ductile metals and alloys undergo plastic yielding at room temperature, during which they exhibit work-hardening and the generation of surface instabilities that lead to necking and failure. We show that pure nanocrystalline copper behaves differently, displaying near-perfect elastoplastic behavior characterized by Newtonian flow and the absence of both work-hardening and neck formation. We observed this behavior in tensile tests on fully dense large-scale bulk nanocrystalline samples. The experimental results further our understanding of the unique mechanical properties of nanocrystalline materials and also provide a basis for commercial technologies for the plastic (and superplastic) formation of such materials.
Champion
Yannick
Y
Centre d'Etudes de Chimie Métallurgique-CNRS, 15 rue Georges Urbain, 94407 Vitry-sur-Seine, France. yannick.champion@glvt-cnrs.fr
Langlois
Cyril
C
Guérin-Mailly
Sandrine
S
Langlois
Patrick
P
Bonnentien
Jean-Louis
JL
Hytch
Martin J
MJ