Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10655613 | Intermetallics | 2010 | 5 Pages |
Abstract
Material systems that exhibit self-propagating exothermic reactions (SPER) can be potentially used for nano/microscale heater purposes in thermal nanomanufacturing applications. We propose that ball milling (BM) is a simple and cost effective technique that can be used to produce such materials. For this purpose, an interrupted BM run of aluminum/nickel powders with a molar ratio of 1:3 was performed, followed by the cold pressing of the powders into pellets that were ignited using an external heat source. Samples that exhibit SPER were characterized before and after ignition using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) with a Back Scattered Electron Detector (BSE), Energy Dispersive X-Ray analysis (EDX) and Differential Thermal Analysis (DTA). The results show that after 7Â h of BM an aluminum/nickel lamellar structure forms at the particle boundaries. The characteristic lamella dimension reduces with increasing milling time down to â¼200Â nm after 10Â h of BM. The ignition conditions for compacts of milled powders indicate that samples with a higher volume fraction of the lamellae possess the shortest ignition time at 4.25Â s.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Anastasia Hadjiafxenti, Ibrahim Emre Gunduz, Chrysostomos Tsotsos, Theodora Kyratsi, Charalabos C. Doumanidis, Claus Rebholz,