Influence of Starting Material Molar Ratio on the Properties of Alumina Powders

YELTEN A., YILMAZ S.

18th International Metallurgy and Materials Congress (IMMC 2016), İstanbul, Turkey, 29 September - 01 October 2016, pp.126-128

  • Publication Type: Conference Paper / Summary Text
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.126-128
  • Istanbul University Affiliated: Yes

Abstract

Alumina (Al2O3) is a high-tech structural ceramic material and can be used in various applications from refractory industry to biomedical needs. Sol-gel is the advanced production method for obtaining alumina powders with high purity at low reaction temperatures. In this study, alumina powders were synthesized by using aluminum isopropoxide (AIP, (AlOC3H7)3) and aluminum nitrate nonahydrate (Al(NO3)3.9H2O) as the starting materials. Influence of (NO3¯/Al3+) molar ratio was investigated by preparing sols with (NO3¯/Al3+) molar ratio as 0.5, 0.86 and 1.0. Hydrolysis and peptization reactions were completed in one step at 85-90 °C instead of two which enables a practical synthesis procedure. After hydrolysis&peptization step, gelation at 110 °C and heat treatment at 1300 °C were carried out, respectively. Characterization of the produced powders includes X-Ray Diffraction (XRD) analyses for the chemical properties, Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) for microstructure observations-elemental analyses and Fourier Transform Infrared Spectroscopy (FTIR) for evaluation of the molecular bonding properties.