Impact of Nanoengineered Surfaces of Carbon-Bonded Alumina Filters on Steel Cleanliness

Abstract

Using a special steel casting simulator, carbon-bonded alumina filters are immersed in a steel melt, which contains artificially-generated endogenous alumina particles. Uncoated and MWCNTs-coated ceramic filters are dipped and rotated for 10 and 300 s in the melt at 1 650 °C. Before and after the immersion test, the same samples are analyzed by means of computer tomography, in order to investigate the kinetic of inclusions deposition on the filter surface and possibly to measure the thickness of the in situ formed layers as a function of the immersion time. In addition, samples of the solidified steel are taken after the tests and analyzed by light and electron microscopy. The population of detected inclusions is classified in terms of size and chemistry in order to compare the filtration efficiency of the carbon-bonded filters.