SPS反应烧结HfB2复合材料的制备和性能

Preparation of HfB2-ZrSi2-SiC Composites by Reactive Spark Plasma Sintering and Its Properties

针对HfB2陶瓷材料难烧结和韧性差等问题,选择ZrC粉、Si粉和C粉为烧结助剂,借助ZrC-Si-C间的原位反应生成ZrSi2和SiC,促进HfB2陶瓷的烧结,并提高HfB2陶瓷的综合力学性能。结果表明,HfB2与烧结助剂的混合粉体经放电等离子烧结(SPS)在1600℃保温10 min和40 MPa的压力条件下制备出相对密度为96.6 1%的HfB2-ZrSi2-SiC复合材料,所制样品的硬度、抗弯强度和断裂韧性均随着烧结助剂ZrC-Si-C含量的增加呈现先上升后降低的趋势。当ZrC-Si-C添加量为10%时所制备样品的综合力学性能最好,其硬度值为26.80±1.2 GPa、抗弯强度为504±40 MPa、断裂韧性值为4.66±0.21 MPa·m1/2。

ZrC,Si and C powders were used as the sintering aids to enhance the densification and the mechanical properties of HfB2,using the in-situ reaction between ZrC-Si-C at sintering temperature.The result shows dense HfB2-ZrSi2-SiC ceramic composites are fabricated by reactive spark plasma sintering at 1600℃ for 10 min under a pressure of 40 MPa.With increasing the amount of ZrC-Si-C,the Vickers hardness,the flexural strength and fracture toughness of the sintered samples increase first,and then decrease.HfB2-10 wt% ZrC-Si-C composite shows the best comprehensive mechanical properties.The Vickers hardness,flexural strength and fracture toughness of HfB2-10% ZrC-Si-C composites are 26.80±1.2 GPa,504±40 MPa and 4.66±0.21 MPa·m1/2,respectively.