轧制变形量对GNPs/Ti复合材料组织与性能的影响

Effects of Hot-rolling Reduction on Microstructure and Mechanical Properties of GNPs/Ti Composites

摘要:

本文采用放电等离子烧结技术(SPS)和热轧制备了石墨烯/钛基复合材料(GNPs/Ti)。重点研究了轧制变形量对GNPs/Ti复合材料的显微组织及力学性能的影响规律。采用扫描电镜观察不同变形量后的显微组织,结果显示,随着轧制变形量的增加,基体晶粒长径比增大,石墨烯取向性提高。拉伸结果表明,GNPs/Ti复合材料的抗拉强度和断后伸长率随着变形量的增加而增加,最大抗拉强度达到680MPa,相比纯钛提高了33%。采用轧制工艺可以使GNPs/Ti复合材料孔洞减少、GNPs分布具有取向性,从而提高材料的力学性能。

Abstract:

Graphene nanoplatelets (GNPs)/Ti composites were fabricated by spark plasma sintering (SPS) and hot-rolling. This work was focused on the effects of rolling reduction on microstructure and mechanical properties of GNPs/Ti composites. The SEM microstructure results showed that matrix grains were gradually elongated and the amount of GNPs which were along the rolling direction rose with the increase of rolling reduction. The tensile test results show that the ultimate tensile strength and fracture elongation of the GNPs/Ti composites increase with the increase of rolling reduction. The ultimate tensile strength of the composites with 60% rolling reduction is 680MPa, which is increased by 33% compared with pure Ti. Hot-rolling process can relieve defects and lead to GNPs aligned along the rolling direction, which contribute to the improvement of the tensile property.