Comparing the Strength of FCC and BCC Submicron Pillars : Compression Experiments and Dislocation Dynamics Simulations

Content Provider	Semantic Scholar
Author	Greer, Julia R. Weinberger, Christopher Robert
Copyright Year	2007
Abstract	We compare mechanical strength of FCC Gold and BCC Molybdenum single crystal pillars of sub-micron diameter in compression tests. Both crystals show an increase of flow stress with decreasing diameter, but the change is more pronounced in Au compared with Mo. The ratio between the observed maximum flow stress and the theoretical strength is much larger in Au pillars than in Mo pillars. Dislocation Dynamics (DD) simulations also reveal different dislocation behavior in these two metals. While in an FCC crystal a dislocation loop nucleated from the surface simply moves on its glide plane and exits the pillar, in a BCC crystal it can generate multiple new dislocations due to the ease of screw dislocations to change slip planes. We postulate that this difference in dislocation behavior is the fundamental reason for the observed difference in the plastic deformation behavior of FCC and BCC pillars.
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://micro.stanford.edu/~caiwei/papers/Greer_Weinberger_Cai_MSEA_08_FCCBCC.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article