高岭土制备β-sialon粉体的影响因素

INFLUENCING FACTORS OF THE PREPARATION OF β-SIALON POWDERS BY KAOLIN

以南宁维罗高岭土为原料,分别利用精细化高岭土和原矿作原料,采用碳热法,在1450℃经氮化合成一定质量分数β-sialon粉体。对氮化工艺过程和合成产品的物相进行分析。结果表明:采用精细化高岭土和原矿均可生成一定质量分数β-sialon粉体;以不同原料合成的产品中,杂相铝硅酸盐含量有明显不同;添加适量Fe_2O_3可抑制铝硅酸盐含量。用精细化处理的高岭土为原料,N_2平均流量为112.5L/min时,合成的β-sialon粉体含量高,产品中的铝硅酸盐、莫来石和β-sialon的质量比为1:0.5:1.5。

Sample of β-sialon powders with certain mass fraction were synthesized by the carbothermal method through nitridation at 1450℃ in a tubular furnace utilizing refined kaolin and kaolin rough ore from Guangxi Weiluo as raw materials. The nitridation process and phase state of the product were analyzed. The results show that β-sialon powders with certain mass fraction can be prepared using refined kaolin and kaolin rough ore as raw materials. The content of aluminosilicate impurity in the product prepared using different raw materials is obviously different. The aluminosilicate can be restrained via appropriate addition of Fe2O3. Using refined kaolin as raw materials, when the average flow of N2 is 112.5 L/min, the content of synthesized β-sialon is highest, and the mass ratio of aluminosilicate and mullite and β-sialon is 1：0.5：1.5.