The effect of B2O3 on the crystallization of zirconium titanate

Crystallization of coprecipitated zirconium-titanium hydroxide in the presence of the B2O3 melt as far as its action on ZrTiO4 powder and ceramics was studied by XRD and SEM investigations. It was found that ZrTiO4 formation from the X-ray amorphous ZT precursor is inhibited by the presence of liquid B2O3 leading to ZT decomposition, yielding Zr(Ti)O2 and Ti(Zr)O2 substitutional solid solutions. The concentration of substituents continuously decreased up to 4 mol% with increasing temperature. The decomposition process was followed by the change of oxide particle morphology due to recrystallization via incongruent dissolution of oxide phases in the B2O3 melt. Crystalline ZrTiO4 (powders and ceramics) were also found to be decomposed by the B2O3 melt treatment.

Keywords:

• Zirconium titanate
• zirconium oxide
• titanium oxide
• boron oxide
• zirconiumtitanium hydroxide
• unit cell volume
• X-ray phase analysis
• electron microscopy
• powder

Notes

Present address: Israel Ceramic and Silicate Institute, Technion City, Haifa 32000, Israel.