Powder Technology, Vol.235, 717-722, 2013
New anhydrous aluminum nitride dispersions as potential heat-transferring media
Aluminum nitride was found to be of great significance in advanced ceramics. A widely applicable semiconductor, AlN is also commonly known for its considerable heat conductivity, as high as 320 W/(m.K). The idea behind the studies was to use AlN dispersions as a heat transferring liquid in closed systems. Such a liquid heat-carrier should give a proper rheological response when under variable shear-temperature conditions. Contrary to other systems reported in literature, i.e. nanolluids [1-20], the systems presented consisted of AlN micropowder and some novel base liquids: poly(propylene glycols) with an average molecular weight of 425 and 2000. The optimal result was to produce dispersions which display Newtonian-like flow at increased temperature and shear rate, as well as a suitable AlN concentration with sustained time-stability. This compilation of research assumptions should result in intensified heat exchange capabilities of liquid transferring media made on the basis of aluminum nitride. (C) 2012 Elsevier B.V. All rights reserved.
Keywords:Aluminum nitride;Thermal conductivity;Heat-transferring liquid;Non-Newtonian flow;Viscosity;Thixotropy