Acta Metallurgica Sinica (English Letters) ›› 2021, Vol. 34 ›› Issue (2): 196-204.DOI: 10.1007/s40195-020-01138-5

Previous Articles     Next Articles

Dispersion and Damage of Carbon Nanotubes in Carbon Nanotube/7055Al Composites During High-Energy Ball Milling Process

S. Bi1,2, B. L. Xiao1, Z. H. Ji1,2, B. S. Liu3, Z. Y. Liu1(), Z. Y. Ma1   

  1. 1Shi-changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016, China
    2School of Material Science and Engineering, University of Science and Technology of China, 72 Wenhua Road, Shenyang, 110016, China
    3AVIC Manufacturing Technology Institute, Beijing, 100024, China
  • Received:2020-04-09 Revised:2020-06-28 Accepted:2020-07-07 Online:2021-02-10 Published:2021-02-09
  • Contact: Z. Y. Liu

Abstract:

High-energy ball milling (HEBM) combined with powder metallurgy route was used to fabricate carbon nanotube (CNT) reinforced 7055Al composites. Two powder morphology evolution processes (HEBM-1 and HEBM-2) were designed to investigate the dispersion and damage of CNTs during HEBM process. HEBM-1 evolution process involved powder flattening, cold-welding and fracture, while HEBM-2 evolution process consisted of powder flattening and fracture. For HEBM-1, the repetitive fracture and cold-welding process was effective for dispersing CNTs. However, the powder flattening process in HEBM-2 was unsuccessful in dispersing CNTs due to two reasons: (1) the thickness of flaky Al powders exceeded the critical value, and (2) the clustered CNTs embedded in flaky Al powders could not be unravelled. Because of the broadening of D band and the appearance of a new defect-related D’ band, product of ID/IG and full width half maximum of D band, rather than ID/IG, was used to evaluate the actual damage of CNTs. It indicates that the damage of CNTs was severe in powder flattening and fracture stages, while the damage of CNTs was small in powder cold-welding stage.

Key words: Metal matrix composites, Carbon nanotubes, Powder evolution, Dispersion and damage, Powder metallurgy