石墨烯增强TC4复合材料的微观组织及力学性能

Microstructure and Mechanical Properties of Graphene Reinforced TC4 Composites

摘要:

采用球磨法将石墨烯与TC4预合金粉末混合,通过放电等离子烧结工艺在1 200℃制备了石墨烯/TC4复合材料。采用扫描电子显微镜、X射线衍射仪等研究了复合粉末混合前后的形貌和物相结构;采用显微硬度计、Gleeble-3800D热模拟试验机等分析了复合材料的显微硬度和压缩性能。结果表明:通过干法球磨和放电等离子烧结工艺制备的复合材料组织致密,石墨烯与TC4原位生成的TiC在晶界处析出,提高了复合材料的力学性能。复合材料的室温压缩强度和屈服强度,相对于基体分别提高了17.03%和12.5%;硬度和延伸率分别提高了18.2%和60%。石墨烯的加入使得TC4基体晶粒细化,同时与基体反应生成了TiC颗粒,对基体产生了强化效果。

Abstract:

Graphene and TC4 prealloyed powders were mixed by ball milling method. Then, spark plasma sintering(SPS) process was applied at 1 200 ℃ to fabricate graphene/TC4 composites. The morphology and phase structure of the composite powder were investigated by scanning electron microscopy(SEM) and X-ray diffraction(XRD). The microhardness and compression performance of the composites was also analyzed by microhardness tester and Gleeble-3800 D. The results show that the graphene/TC4 composites are compact and graphene and TiC generated in situ from TC4 precipitate at the grain boundaries, which improves the mechanical properties of the composites. The compression strength and yield strength of the composites at room temperature are increased by 17.03% and 12.5% compared with the matrix. Hardness and elongation are increased by 18.2% and 60% respectively. The addition of graphene refines the grain and reacts with the matrix to generate TiC particles, which enhanced the matrix.