Show simple item record

dc.contributor.authorGu, Junhua 18:38:07 (GMT) 18:38:07 (GMT)
dc.description.abstractThe mechanical properties of nano-crystalline copper pillars were investigated by both experimental methods and Molecular Dynamic Simulations in this study. Electron beam lithography and electroplating were used to fabricate the nano-crystalline copper pillars with various cross-sectional geometries, namely solid core, hollow, c-shaped, and x-shaped. These as-fabricated copper pillars possess three different average grain sizes, which were achieved by changing the compositions of the plating solution. Uniaxial micro-compression tests were applied to deform these nano-crystalline columnar structures. Classical Hall-Petch relationship was observed between the large-grain specimens and medium-grain specimens. An inversed Hall-Petch relationship emerged as the grain size continued to go down to the small grain size region. The mechanical behavior exhibited no signs of sensitivity to the cross-sectional geometries. To understand the deformation mechanisms, Molecular Dynamic Simulations were performed on nano- crystalline copper pillars with different dimensions. The as-constructed models displayed different mechanical behaviors under compressive and tensile deformation. This so-called compression-tension asymmetry was believed to be associated with free surface alongside the nano-crystalline pillars, where the free surface energy made opposite contributions under compression and tension. An inversed Hall-Petch trend was also observed between the nano-crystalline copper columnar structure with the grain size of 13 and 6 nm.en
dc.publisherUniversity of Waterloo
dc.subjectMolecular Dynamic Simulationen
dc.titleRevealing the Mechanical Properties of Metal Pillars Using Experimental Methods and Molecular Dynamic Simulationsen
dc.typeMaster Thesisen
dc.subject.programChemical Engineering (Nanotechnology)en Engineeringen
uws-etd.degreeMaster of Applied Scienceen

Files in this item


This item appears in the following Collection(s)

Show simple item record


University of Waterloo Library
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
519 888 4883

All items in UWSpace are protected by copyright, with all rights reserved.

DSpace software

Service outages