Spinal and Spinel-zirconia Composite Material Prepared at Low Temperature by Al13 as Aluminium Source

Spinel and spinel-zirconia composite powder were synthesized by soft chemistry method using ￡ lO4Al12(OH) 24(H2O) 12￡ SUP>7+￡¨abbreviated Al13￡ as aluminum source. Precursor structure, reaction progress and material microa2structure evolvement were characterized by 27Al NMR, XRD, DSC-TG and FTIR. Spinel precursor was prepared by mixing Al13 solution and magnesium slurry which was obtained by milling the mixture of MgCl2 ¤6H2O and NaOH, and its component included Mg6Al2CO3(OH)16 ¤4H2O and |-Al(OH)3. Spinel is formed from calcination of this spinel precursor at 600 or 1h, and only spinel is formed at even higher temperatures. Spinel-zirconia composite powder precursor is prepared by hydrolysis-precipitation process of Al13, MgCl2 ¤6H2O and ZrOCl2 ¤8H2O solution. Spinel-zirconia composite powder can also be obtained from calcination of the precursor at 600 FTIR spectra of the Al13 powder and spinela2zirconia precursor show that the ￡ lO6￡ absorption band shifts from 608cm-1 to 601cm-1 and ￡ lO4￡ from 761cm-1 to 723cm-1.The result shows that Al13 has obvious advantage in synthesis of spinel and spinela2zirconia composite powders at low temperature because Al-O-Mg bond can be formed easily in precursors.