高温熔体浇注合成TiC颗粒局部增强Al基复合材料

TiC Particulates Locally Reinforced Al-matrix Composites by High-temperature Melt Casting

将铸造法与原位反应法相结合,利用高温Al液诱发Al-Ti-C压块反应而生成Ti C,进而原位制备了Ti C颗粒局部增强Al基复合材料,并结合DSC及其截断处理分析了该体系生成Ti C相的反应行为。结果发现:当Al含量为20~40wt%时,Al-Ti-C体系能发生反应而生成Ti C颗粒,而Al含量低于10wt%或高于50wt%时该体系不能发生Ti C的形成反应。Ti C/Al基复合材料局部增强区的界面上Ti C颗粒细小弥散、逐步自然过渡,且与Al基体结合紧密。DSC分析证实,Al-Ti-C体系中的Al粉能细化生成的Ti C颗粒,同时还参与了Ti C相的形成反应。

Combining the casting with the in-situ reaction, TiC was produced by the reaction of the Al-Ti-C compacts induced by the high-temperature Al melt, and thus the TiC particulates locally reinforced Al-matrix composites were in-situ fabricated. The reactive behavior to form the TiC phase from the Al-Ti-C system was analyzed by DSC and its truncation treatment. It is found that, the Al-Ti-C system could react to generate TiC particulates with the 20-40wt% Al content, but the TiC formation reaction fails if the Al content is below 10wt% or above 50wt%. At the interface of the locally reinforced region in the TiC/Al composites, TiC particulates exhibit the fine and uniform distribution and tight adhesion with Al-matrix, and also the interface appears the natural and gradient transition between the reinforced region and Al-matrix. Through DSC analysis, it is proved that the A1 powders in the Al-Ti-C system not only refine the formed TiC particulates, but also participate in the formation reaction of the TiC phase.