TiB₂-B₄C复合陶瓷动态压缩特性研究

In order to study the dynamic mechanical properties of TiB₂-B₄C composite and the effect of additive TiB2 on the mechanical properties, a series of static/dynamic compression experiments and plate impact experiments were designed to evaluate the dynamic compression property of the composite at different strain rates. Experimental results show that the TiB₂-B₄C composite is a brittle material as ceramic. The stress-strain relations of the composite show a typical linear characteristic. The Hugoniot elastic limit of the composite is increased from 14.98 to 16.91 GPa with the increass in loading strain rate. When the loading rate is lower than 10³ s^-1, the dynamic compression strength of TiB₂-B₄C composite is higher than those of the pure B₄C and pure TiB₂ ceramic, and it has a positive strain rate sensitivity under one-dimensional stress wave loading. The increase in compression strength of the composite benefits from the improvement of the microstructure. The strain rate sensitivity is mainly controlled by the additive TiB₂ which serves as a strengthening and toughening agent. However, when the loading rate is higher than 10⁴ s^-1, the Hugoniot elastic limit of TiB₂-B₄C composite is close to that of the matrix B₄C, and is little affected by the additive TiB₂.