TiCp/ZA-12复合材料凝固时TiCp的行为

利用XD法与搅拌铸造技术相结合的工艺制备TiCp/ZA-12复合材料，采用常规凝固与定向凝固的技术研究增强粒子TiCp在凝固界面的行为，结果表明，常规凝固条件下，TiC含量较低时，颗粒主要分布于共晶相内，TiC含量较高时，颗粒不仅存在于共晶相内，也存在初生相内，定向凝固条件下，由于初生相对TiC的排斥作用使TiCp/ZA-12复合材料凝固组织中存在TiC聚集的带状组织，TiCp在带状组织中的聚集程度与TiC含量有关，随TiCp含量增加，聚集程度减小，当TiCp含量超过6％后，聚集带已不明显。

The Behavior of TiCp During TiCp/ZA-12 Composites Solidification

TiC p/ZA 12 composites have been fabricated by XDTM and stirring casting techniques. The behavior of TiC reinforcement particle in the solidification interface has been studied during the traditional and directional solidification respectively. The research results can be described as follows: under traditional solidification conditions, TiC particles mainly distribute in eutectic phases at lower fraction of TiC particles, however, TiC particles exist not only in eutectic phases but also in primary phases at higher fraction of TiC particles; under directional solidification, there are congregated TiC particles having band structure in solidification microstructure of TiC p/ZA 12 composite due to the pushing function of primary phases of alloy on TiC particles. The extent of congregation of TiC particles in band structure correlates with TiC particles fraction. With the increase of TiC particles, the extent of congregation of TiC particles in band structure decreasces. When the fraction of TiC particles reaches higher than 6%, the band structure disappears.