It has been known for some time that the resistance to plastic deformation increases as dimensions approach the submicrometer scale. The most dramatic effect has been discovered most recently in nanometer-sized Au contacts whose ultimate strengths are comparable to those of the hardest metallic materials known. We show in this Letter that topological material hardening is a general phenomenon originating from the one-dimensional nature of dislocations. Consequently, the corresponding mechanical stresses scale inversely with dimension. At a length scale of typically 10 nm the stresses become comparable to the intrinsic lattice strength. Below this crossover point, dislocations are suppressed completely, and plastic deformation proceeds by a collective slip of entire atomic planes and ultimately by order-disorder transitions. Topological hardening has far-reaching implications, particularly in the context of nanostructured
By: U. Duerig and A. Stalder
Published in: RZ2873 in 1996
LIMITED DISTRIBUTION NOTICE:
This Research Report is available. This report has been submitted for publication outside of IBM and will probably be copyrighted if accepted for publication. It has been issued as a Research Report for early dissemination of its contents. In view of the transfer of copyright to the outside publisher, its distribution outside of IBM prior to publication should be limited to peer communications and specific requests. After outside publication, requests should be filled only by reprints or legally obtained copies of the article (e.g., payment of royalties). I have read and understand this notice and am a member of the scientific community outside or inside of IBM seeking a single copy only.
Questions about this service can be mailed to reports@us.ibm.com .