Investigation of ballistic impact properties and fracture mechanisms of Ti<sub>3sub>SiC<sub>2sub> ternary ceramics
- 作者：Wen-Tse Lo ; Ching-An Jeng ; Jow-Lay Huang ; Horng-Hwa Lu ; Ding-Fwu Lii
- 关键词：Ti<sub>3sub>SiC<sub>2sub> ternary ceramics ; Ballistic impact ; Fracture mechanisms ; Microstructure ; Mechanical properties
- 刊名：Journal of Alloys and Compounds
- 出版年：2008
- 期刊代码：45_09258388
- 类别：ms
- 出版时间：8 May 2008
- 卷：455
- 期：1-2
- 页码：413-419
- 文件大小：1376 K
摘要
The deformation response of Ti<sub>3sub>SiC<sub>2sub> ternary ceramics have been investigated by performing ballistic impact experiments at a range of low velocities. The reactively hot pressing compacts with an off-stoichiometric ratio were predominantly Ti<sub>3sub>SiC<sub>2sub> phase (99.13 vol.%) and the grains were elongated in shape with a grain size of 3–8 bc;m. The bulk modulus (196 GPa) was slightly lower than that calculated by fitting the pressure versus lattice volume data with the Birch–Murnaghan equation (206 GPa), and that predicted by using the first-principle computational technique (204 GPa). The typical fracture surface of the fragments was failed by transgranular fracture combined with intergranular fracture. Most fracture mechanisms were similar to energy-absorbing mechanisms observed in the vicinity of the indentation. The dynamically impacted fragments of Ti<sub>3sub>SiC<sub>2sub> contained dislocations and stacking faults, grouped in bands extending from the grain boundaries and ending in the grain. The Si plane was depleted and the remaining thin lamella consisted of six close-packed Ti planes, with five C planes in-between, showing identical stacking as b;1 1 1} planes in TiC. The Hugoniot elastic limit and the hydronamic pressure at the HEL point were estimated to be 6 and 3 GPa, respectively.