The red space at the top of this photo is a piece of steel weighing 200 grams ( a little less than half a pound ) heated to 800 degrees centigrade . The ceramic lattice holding the weight weighs only 0.04 grams . The ability to create strong , high temperature structures is a big reason for designing and building at the nano level and scaling up . Materials built at larger scales have weaknesses and deficiencies which cause them to lose their beneficial properties . for many applications , due to their dimensional constraints they have been limited to one or two-dimensional forms . When these nanowires and thin films are scaled up , their size-affected properties are lost , and when they are clustered in a composite , interfaces and matrix materials weaken their overall performance . To overcome this dilemma researchers envision highly ordered three-dimensional architectures constructed from these miniaturized features .
It is to this nano-world that Rayne Zheng , assistant professor of mechanical engineering in the College of Engineering , wants to take 3-D printing , a technology many people are familiar with from the millimeter world . Zheng was recently given a three-year National Science Foundation grant to study what it would take to build complex three-dimensional structures at the nano-level and then scale them up to micrometer , millimeter scales and above .
In traditional manufacturing techniques , many beneficial properties originated from the nanoscale are lost during the scaling up process . “ We ’ re investigating the additive manufacturing process that underpins this scaling up process – allowing optimal control of hierarchical feature sizes so that nanoscale features , can be transferred into any arbitrary three-dimensional architectures , with minimal loss of their pristine properties ,” Zheng said . “ We ’ re looking at questions like , how do we achieve printing below the micrometer level and achieve scalable , microand nano-manufacturing techniques that excel at incorporating multiple , diverse materials .”
The key driving force is the evolution of high precision additive manufacturing technologies , which have been used to create 3-D micro-architected materials . In a recent publication by Zheng ’ s group , these materials use an engineered micro-structure , rather than relying on chemistry alone , to provide designed properties and performance . The understanding of metamaterials has rapidly advanced , with modeling , simulation , and design tools , and basic
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