HA-ZrO_2复合陶瓷烧结致密化过程中的晶粒行为

The Grain Behavior of HA-ZrO_2 Composite Ceramics in Sintering Densification Process

利用球磨法配制HA-ZrO2复合陶瓷浆料,通过自由成形制备试样,干燥后进行无压烧结,测试烧结性能,并对材料微观形貌和相组成进行分析。研究了不同体积比下HA-ZrO2复合陶瓷烧结过程中两种晶粒间相互作用及其对致密性能的影响,探索了烧结后晶粒相结构的变化。结果表明:随ZrO2含量增加,复合陶瓷力学性能显著提高,抗弯强度最高可达371.42 MPa,致密度总体呈上升趋势,可达93.14%,当HA-ZrO2体积比为4∶6到6∶4之间时,其致密度出现下降的现象;烧结过程中由于Ca2+的掺杂使得复合陶瓷中ZrO2以立方相存在,减弱了相变增韧作用。

HA-ZrO2 composite ceramic slurry was prepared by ball-milling. Ceramic samples were fabricated by free from fabrication and pressurelessly sintered in the temperature range 1200-1400℃ after drying. Sintering performance was tested, material microstructure and phase composition were analyzed. The effect of ZrO2 volume ratio on the interaction between the two grains in sintering process was studied and the phase change was investigated. The results indicate that with the increase of ZrO2, the mechanical properties of composite ceramics significantly increased and maximum flexural strength was 371.42 MPa, while the relative density of composite ceramics overall showed an upward trend and the maximum was 93. 14%. But when HA and ZrO2 volume ratio ranged from 4：6 to 6： 4, the density decreased. The existence of the cubic zirconia was due to the Ca2＋ doped in the sintering process, while the effect of phase transformation toughening was weakened.