原位反应制备Al_2O_3弥散强化ZrO_2基复合陶瓷

Al_2O_3 Dispersion Strengthened ZrO_2 Matrix Composite Ceramic Prepared By In-situ Reaction

为降低氧化锆基陶瓷烧结温度和提高其力学性能,在氧化锆中加入不同含量的纳米铝粉并采用在不同微波烧结温度使铝发生原位反应生成氧化铝弥散强化氧化锆基体的方法制备了Al_2O_3/ZrO_2复合陶瓷。通过XRD物相分析、SEM显微结构观察和力学性能等测试,得到了纳米铝粉含量和微波烧结温度对Al_2O_3/ZrO_2复合陶瓷力学性能和显微结构的影响规律。结果表明:ZrO_2基复合陶瓷素坯较适合的排塑温度为400℃。在保温时间30 min条件下,纯ZrO_2陶瓷和Al_2O_3/ZrO_2复合陶瓷的较佳微波烧结温度为1 350℃。纳米铝粉添加体积含量为0.5%的Al_2O_3/ZrO_2复合陶瓷具有较佳的综合性能,其致密度为98.56%,硬度为14.92 GPa,抗弯强度为607.07 MPa,断裂韧性为15.09 MPa·m^(1/2),抗弯强度和断裂韧性分别提高了10.46%和16.62%。

To reduce the sintering temperature and improve mechanical properties of ZrO_2-based ceramics,adding different contents of nanometer aluminum powder in ZrO_2,Al_2O_3/ZrO_2 composite ceramics was prepared by in situ reaction of Al_2O_3 dispersion strengthening ZrO_2 matrix phase at different microwave sintering temperatures.The influences of the nano-aluminum powders contents and sintering temperatures on the microstructure and mechanical properties of Al_2O_3/ZrO_2 composite ceramics were obtained By XRD phase analysis,SEM microstructure observation test,mechanical properties,and so on.The results show that the suitable binder remove temperature of ZrO_2 matrix composite ceramic is 400 ℃.The optimized microwave sintering temperature of pure ZrO_2 and Al_2O_3/ZrO_2 composite ceramics is 1 350℃ under the condition of the holding time of 30 min.Al_2O_3/ZrO_2 composite ceramics with the addition of 0.5 vol% nanometer aluminum powder has better comprehensive properties.The density,hardness,bending strength and fracture toughness of it are 98.56%,14.92 GPa,607.07 MPa,15.09 MPa·m1/2,respectively.Compare to pure ZrO_2,its bending strength and fracture toughness increased by 10.46% and 16.62%,respectively.