磷酸铬铝粘结剂的制备及其热处理中的相变

Preparation of Chromium-Aluminum-Phosphate Binder and Phase Evolution during Heat Treatment

以Al(OH)3、H3PO4、CrO3和CH3OH为原料制备磷酸铬铝,通过对反应体系粘度及其吸潮率、热失重率的监测,确定反应的物质的量比、温度及反应时间。采用DTA-TG、IR和XRD分析研究了体系的固化特性和耐热性能。结果表明,反应的最佳条件为:反应温度80℃,n(Al(OH)3)∶n(H3PO4)∶n(CrO3)=3∶9∶1,反应时间为1h。磷酸铬铝粘结剂在300～1000℃时是非晶相,1100℃时是Cr(PO3)3和AlPO4两种晶型,1200℃时是Cr4(P2O7)3和AlPO4两种晶型。

The aluminum-chromium-phosphate（ACP） was synthesized with aluminum hydroxide chromic oxide and phosphoric acid as original materials. The viscosity of the reaction system, moisture absorption rate and weight loss rate was monitored to control extent of the reaction. The DSC-TG, IR and XRD techniques were used to analyze the ACP properties. The experimental results show that the phase evolution of the consolidated products as： amorphous phase in 300-1000℃, Cr（POa ）3 and AlPO4 in 1100℃, Cr4 （P2 O7）3 and AlPO4 in 1200℃ for aluminum chro mium-phosphate system binder.