烧结温度对增材制造精密铸造型壳材料性能的影响

Influence of Sintering Temperature on the Properties of Precise Casting Shell Prepared by Additive Manufacturing

基于陶瓷浆料挤出成形的增材制造工艺制备了精密铸造型壳材料试样,通过XRD和SEM研究了烧结试样的相组成和断口形貌,并对比了烧结温度对型壳材料性能的影响。结果表明,烧结温度从900℃升高到1000℃,型壳材料的抗弯强度迅速提高,超过1000℃后基本稳定;随着烧结温度的升高,孔隙率不断减小、收缩率不断增大。确定的型壳材料的烧结温度为1000℃,试样的抗弯强度为7.31 MPa、孔隙率为43.6%、平均收缩率为0.79%。型壳材料烧结后的强度提高,主要来源于硅基粘结剂的结晶化转变及莫来石相数量的增加。

The precision cast shell material samples were prepared by the additive manufacturing process of ceramic slurry extrusion forming.The phase composition and fracture morphology of the sintered samples were studied by XRD and SEM,and the influence of sintering temperature on the properties of the molded shell material was compared.The results show that when the sintering temperature increase from 900℃to 1000℃,the bending strength of the molded shell material increase rapidly and is basically stable after it exceed 1000℃.With the increase of sintering temperature,the porosity decreases and shrinkage increases.The sintering temperature of the shell material determined is 1000℃,the bending strength of the sample is 7.31 MPa,the porosity is 43.6%,and the average shrinkage is 0.79%.The increase of strength of molded shell material after sintering is mainly due to the crystallization transformation of silicon-based binder and the increase of mullite phase.