原位合成纳米氧化铝烧结助剂制备轻质氧化铝陶瓷

PREPARATION OF LIGHTWEIGHT ALUMINA CERAMIC AND IN-SITU SYNTHESIS OF NANOMETER ALUMINA POWDERS AS SINTERING AGENT

采用氧化铝空心球和α -Al2 O3细粉为原料 ,以硫酸铝和硫酸铝铵水溶液及PVA水溶液为结合剂 ,并以硫酸铝和硫酸铝铵受热分解而原位合成的纳米γ -Al2 O3作为烧结助剂制备轻质高强氧化铝陶瓷。研究结果表明 :引入的氧化铝空心球助烧剂能促进轻质高强氧化铝陶瓷的烧结 ,烧结温度为 170 0℃ ,对应密度为 1.2 1～ 1.60 g/cm3,常温抗压强度为 2 2～ 42MPa ,荷重软化温度超过 170 0℃ (0 .1MPa) 。

The lightweight alumina ceramic was prepared with alumina bubble and α-Al2O3 powder as raw materials, and solutions of Al2(SO4)3&middot18H2O and NH4Al(SO4) 2&middot12H2O and PVA as the cements, which will form in situ the nano γ-Al2O3 particles to decrease the sintering temperature as sintering agent and improve the strengthen of the ceramics. The strength of the lightweight alumina ceramic reaches 22-42 MPa whose relative density is 1.21-1.60 g/cm3 in normal temperature. The sintering temperature is 1700°C. Refractoriness under load (0.1 MPa) is more high than that at 1700°C. The lightweight alumina ceramic can be used as high-strength inner lining light material of the top temperature kiln.