Study on ZrB2-SiC Prepared by Field Assisted Sintering
ZrB2 and SiC are thought to have a low intrinsic sinterability due to their strong covalent bonds,low bulk and grain boundary diffusivities.ZrB2-SiC ceramic composites were prepared by a field assisted pressureless sintering process in the present work.The densification behavior and the effect of sintering temperature on microstructure and properties of sintered samples were studied.Pellets were in-situ formed by dry uniaxial pressing in the graphite die at a pressure of 50MPa for 3min and then sintered at a sintering temperature ranged from 1650℃ to 1950℃ with fixed heating rate and holding time.The current,voltage,temperature and displacement data were all collected by the real-time acquisition system.The bulk densities were determined by Archimedes method and the microstructure of samples was characterized by SEM.The onset of some measurable shrinkage of the green body was recorded at around 1400 ℃ regardless of the sintering temperature and significant shrinkage took place at higher temperature of around 1600 ℃.For the sample sintered at 1950 ℃,no shrinkage occurred after ~2min holding time.The relative density increased significantly with increasing temperatures and samples could be densified to a relative density of more than 99% at 1950 ℃ by the field assisted sintering process without obvious grain growth.
ZrB2-SiC field assisted sintering densification behavior
Weijun Wang Shizhen Zhu Zhenyu Yan Qiang Xu
School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China National Key Laboratory of Science and Technology on Materials under Shock and Impact,Beijing 100081
国际会议
The Seventh China International Conference on High-Performance Ceramics (第七届先进陶瓷国际研讨会(CICC-7))
厦门
英文
729-734
2011-11-04（万方平台首次上网日期，不代表论文的发表时间）