原位合成的钛合金@CNTs粉体SPS制备TiC/Ti复合材料的微结构与性能

Microstructure and Mechanical Properties of TiC/Ti Composites Fabricated from In-situ Synthesized Ti Alloy@CNTs Powder by SPS

以Fe/Ni为催化剂,利用等离子体增强化学气相沉积(PECVD)方法在球形钛合金微米粉体表面原位合成了碳纳米管(CNTs)包覆的钛合金(钛合金@CNTs)复合粉末。以钛合金@CNTs粉体为原料,利用放电等离子体烧结(SPS)工艺制备了原位TiC与CNTs增强Ti基复合材料,采用扫描电镜(SEM)、透射电镜(TEM)、拉曼光谱仪、X射线衍射仪、电子探针、纳米压痕等对复合粉体及烧结复合材料的微观结构、物相成分及力学性能进行了表征分析。在此基础上探讨了催化剂前驱体含量、生长时间等对低温原位CNTs生长机理的影响,以及复合粉体烧结反应对复合材料组织结构的形成以及CNTs与Ti基体反应原位形成TiC的机理。结果表明,原位形成的TiC主要受CNTs的结晶度与SPS温度所影响。

Carbon nanotubes(CNTs)coated titanium alloy(Ti alloy@CNTs)composite powders were synthesized by in-situ plasma enhanced chemical vapor deposition(PECVD)via Fe/Ni catalyst.The produced composite powders were consolidated via spark plasma sintering(SPS)to fabricate the TiC and CNTs reinforced Ti matrix composites.The microstructure and composition of titanium alloy@CNTs powder were analyzed by scanning electron microscopy(SEM),transmission electron microscopy(TEM)and Raman spectroscopy.The microstructure,phase composition and mechanical properties of the composites were characterized by SEM,XRD,Raman spectroscopy,nano indentation.On this basis,the factors influencing the structure of carbon nanotubes in-situ synthesized by PECVD,including the catalyst concentration and reaction time,were investigated.In addition,the mechanism of the formation of the microstructure of the composite during sintering were discussed and the mechanism of in-situ TiC formation by the reaction of CNTs with Ti matrix.The result indicate that in-situ TiC formation is mainly affected by the crystallinity of CNTs and SPS temperature.