Microstructure and Mechanical Properties of ZrB2-Based UHTC via Reactive Hot Pressing
ZrB2-based ultra-high temperature ceramics (UHTCs) were prepared from a mixture powder of Zr/B4C/Si with different ratio via reactive hot pressing.The experimental results showed that the sintering temperature above 1800℃ was necessary for enhancing the activity of the powders and thus improving the densification of the product.The sinterability and densification properties of ZrB2-based UHTCs meliorated with the amount of Si increasing.However,many large ZrB2 agglomerates formed when the amount of synthesized SiC in the product reached 25vol%,which led to decrease the mechanical property.The composite had highest mechanical properties when the volume ratio of ZrB2∶ SiC∶ ZrC was 73.86∶20∶6.14,and its flexual strength and the fracture toughness were 645.8MPa and 5.66MPa·m1/2 respectively.The microstructure investigation showed the in-situ formed SiC and ZrC were located in the triple point of ZrB2 grains with a size less than 3μm.
ZrB2-based UHTC Reactive hot pressing Microstructure Mechanical property
Qu Qiang Han Wenbo Meng Songhe Zhang Xinghong Han Jiecai
Center for Composite Materials,Harbin Institute of Technology,Harbin 150001,China
国际会议
The Fifth China International Conference on High-Performance Ceramics (第五届先进陶瓷国际研讨会(CICC-5))
长沙
英文
1737-1739
2007-05-10（万方平台首次上网日期，不代表论文的发表时间）