Study on the Microstructure and the Machining Performance of Ti_3SiC_2-TiB_2-TiC Composite Ceramic

摘要

The Ti_3SiC_2-TiB_2-TiC three-phase ceramics are prepared by Spark Plasma Sintering (SPS) method with Self-propagating High-temperature Synthesis (SHS) using Ti, Si, C andB_4C powders. The characterization of sintering product's image and structure is analyzed by XRD and SEM. Most of TiB_2's images are angular cuboid or short bar-shaped and most of TiC phase's images are irregular spherical particles which are evenly embedded in Ti_3SiC_2 substrate and have a good combination interface with Ti_3SiC_2. In the composite ceramic SPS sintering process, sinter sample's displacement along Z-axis goes through three stages of falling, balance and rising along with the change of heating temperature, which reflects the sample's change rule between heated expansion force and pressure. Finally its machining performance is analyzed by wire cutting method and machining method. The Ti_3SiC_2-TiC-TiB_2 block composite ceramic proves to have a good machining performance.