DMAA凝胶体系凝胶注模成型超细ZrO_2陶瓷

Gel-casting of Fine Zirconia Using DMAA Gel System

为了降低传统丙烯酰胺(AM)/N,N-亚甲基双丙烯酰胺(MBAM)凝胶体系的毒性,制备高固相量、低粘度的超细ZrO2(D50=0.19μm)浆料及高性能的生坯和陶瓷,研究了低毒的N,N-二甲基丙烯酰胺(DMAA)/MBAM凝胶固化工艺及pH值和聚甲基丙烯酸铵(NH4PMAA)分散剂对浆料流变性的影响.最终采用低粘度、高固相量、低毒性的浆料制备了性能优异的生坯和陶瓷.浆料的固相量高达56vol%,生坯表面光洁、不起皮、不开裂,强度接近30MPa,其内部颗粒结合紧密,孔径呈单峰分布,ZrO2陶瓷的抗弯强度及断裂韧性分别为960MPa和17.3MPa m1/2,其结构均匀、致密性好、四方相ZrO2含量高.

In order to reduce the toxicity of gelcasting with traditional AM/MBAM Gel system and Prepare high properties green bodies and ceramics.Gelation process of low-toxic DMAA /MBAM system as well as the effect of pH and NH4PMAA on rheological behaviors of slurries were studied.The perfect green bodies and ceramics were prepared using high solid loading slurries with low viscosity and low-toxicity.The solid loading of slurries can be up to 56vol%.The green bodies are surface-smooth without cracking or exfoliation and their bending strength can reach 30MPa.The pore size distribution of the green bodies is single peaked.The mean bending strength of sintered ceramics is 960MPa and the fracture toughness can reach 17.3MPa？m1/2.The zirconia ceramics have good homoge-neity and well dense structure,consisting of more tetragonal ZrO2 phase.