水基氮化硅陶瓷光固化成型工艺研究

Research on Water-based Photocuring Forming Process of Silicon Nitride Ceramic

水基光固化陶瓷浆料的低粘度、高分散是制备致密材料的关键因素。重点讨论了水基光固化中分散剂的种类、pH值、固相含量对光固化Si_3N_4陶瓷浆料流变性能的影响。实验表明:当用0.8 wt%的甲基丙烯酸铵做分散剂,浆料pH=10时,制备出了固相含量40 vol%,粘度为0.8 Pa·s-1的Si_3N_4浆料。通过3D光固化成型技术,运用优化后的浆料制备了形状复杂的涡轮坯体,并在气压烧结1750℃时,获得91%的相对密度,13.76±0.42 GPa的显微硬度和5.32±0.52 MPa·m^(1/2)的断裂韧性。

Low viscosity and high dispersion of water-based photocuring ceramic slurry are the key factors for preparing dense materials.This paper emphatically discusses the influence of the type,pH value,and solid content of dispersantin water-based photocuring on the rheological properties of photocuring Si3N4 ceramic slurry.Experiments show that a Si3N4 slurry with a solid content of 40 vol%and a viscosity of 0.8 Pa·s-1 can be prepared,when using 0.8 wt%Ammonium methacrylate as the dispersant with a slurry pH of 10.A complex-shaped turbine green body was prepared by using the optimized slurry with 3 D light curing molding technology,and 91%relative density,13.76±0.42 GPa microhardness and 5.32±0.52 MPa m1/2 fracture toughness were obtained at 1750℃under pressure.