材料期刊网

以平均粒径20μm 的球状氧化铝为主要原料，去离子水为溶剂，羧甲基纤维素钠为增稠剂（外加质量分数为1％），分别以三聚磷酸钠、六偏磷酸钠、柠檬酸铵为分散剂，变化三种分散剂不同的加入量，制备了三种α-Al2 O3悬浮液。通过测量三种悬浮液沉降1 h 后的沉降量，确定最佳分散剂种类及加入量。选用最佳分散剂及最佳加入量对应的悬浮液为研究对象，在不同 pH 下测量对应的 Zeta 电位，确定最佳 pH；选用最佳分散剂、最佳加入量及最佳 pH 对应悬浮液为研究对象，在不同固含量条件下，测定对应的黏度值，确定最佳固含量。结果表明：不同的分散剂有着不同的分散效果，其中，六偏磷酸钠对悬浮液的稳定效果最好；当六偏磷酸钠的加入量（w）为0．8％～1．0％时，悬浮液沉降量最低，分散效果最好；悬浮液 pH 为10时，其 Zeta 电位最低，稳定性最好；悬浮液固含量为60％（w）时，黏度最低，稳定性最佳。

Three kinds of α-Al 2 O3 suspension were prepared using spherical alumina with an average particle size of 20 μm as the raw material,deionized water as the solvent,sodium carboxymethyl cellulose as the thickener (extra adding 1 mass%),sodium tripolyphosphate,sodium hexametaphosphate,ammonium citrate as the dispersants,varying the dosage of the three dispersants.The sedimentation amounts of the three kinds of suspension after 1 h sedimentation were measured to find the optimal dispersant and its addition;then the best pH value was determined according to Zeta potential;finally,the solid content was optimized according to the viscosity.The results show that:different dispersants have different dispersion effects,the suspension with sodium hexametaphosphate has the best stability;when the sodium hexametaphosphate ad-dition is 0.8 mass% -1.0 mass%,the sedimentation amount is the lowest and the dispersion is the best;when the pH value of the suspension is 10,the Zeta potential is the lowest and the suspension has the best stability;when the solid content of the suspension is 60 mass%,the viscosity is the lowest and the stability is the best.