Microstructures and Properties of Solidified TiC-TiB2 Ceramic Composites with increasing Cr Metallic Binder Prepared by Combustion Synthesis in High-gravity Field
By increasing addition amount of (CrO3 + Al) subsystem in (B4C + Ti) system,the solidified TiC-TiB2 composites with a series of mass fraction of Cr binder were achieved by combustion synthesis in high-gravity field.The microstructures of the solidified ceramics presented a number of fine TiB2 platelets embedded in TiC grains,Cr-Ti alloy or between TiC grains and Cr-Ti alloy.The increased Cr binder in the ceramic not only brought about the enhanced densification of the ceramic due to fill-up of Cr-Ti liquid in shrinkage cavities between solidified TiC and TiB2 phases,but more importantly made fine-grained even ultrafine-grained microstructure achieved because of the accelerated nucleation and the decelerated growth of TiB2 at initial stage of material solidification.As a result of the achievement of fine-grained even ultrafine-grained microstructure along with the enhanced toughneing mechanisms contributed by the refined TiB2 platelets and the increased plastic phases of Cr-Ti alloy,the solifidied TiC-TiB2 composite containing 20.7 % Cr binder presented the maximun values of 1045 ± 25 MPa and 21.5 ± 1.6 MPa · m0.5,simultaneously,in flexural strength and fracture toughness along with the moderate hardness of 17.5 ± 2.2 GPa.
TiC-TiB2 composite metallic binder densification ultrafine-grained microstructures
Liangxiang Liu Long Zhang Zhongmin Zhao Minquan Wang
Mechanical Engineering College,Shijiazhuang 050003,China
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
344-349
2011-11-04（万方平台首次上网日期，不代表论文的发表时间）