2006•Natural Science Journal of Xiangtan UniversityRequires access
Preparation of t-ZrO_2/Al_2O_3 Nanometer Composite Powder via Coprecipitation Method
Lixin Yang
Open publisher page 0 citations
Abstract
With NH_4Al(SO_4)_2·12H_2O,ZrOCl_2·8H_2O and NH_4HCO_3 as raw materials,the nanometer composite powder t-ZrO_2/Al_2O_3 was fabricated by means of coprecipitation.The suitable preparation temperature of precursor was 45 ℃.The molar ratios of NH_4HCO_3/(Zr+Al) had a notable impact on the precipitation rates of zirconium in reaction.After precursor was calcined at 1 100 ℃ for 1 hour,the broaden diffraction peaks of t-ZrO_2 and γ-Al_2O_3 appeared,t-ZrO_2 was relatively uniformly dispersed in alumina,and the grain sizes of both phases were between 10-20 nm.Sample further heated to 1 200 ℃,α-Al_2O_3 phase rapidly formed and accompanied the blend of crystallites in part.