Novel SolidStir extrusion technology for enhanced conductivity cable manufacturing via in-situ exfoliation of graphite to graphene

Abstract

Electrification is a path towards decarbonization. Identification of novel nanocarbon materials such as graphene or carbon nanotubes (CNTs) offers great potential as a reinforcement material in metal matrix composites (MMCs) due to their superior strength and electrical properties. However, challenges exist in achieving uniform dispersion of graphene during manufacturing. Traditional methods and advanced techniques like chemical vapor deposition or spark plasma sintering have limitations in terms of cost and scale of production. In this research, a friction-stir based novel SolidStir® Extrusion (SSE) technique was used for the in situ synthesis of Al-graphene MMC cables. Key factors and phenomena driving the exfoliation process that leads to graphite → graphene conversion during SSE were studied by comprehensive characterization techniques such as Raman spectroscopy and transmission electron microscopy. A constitutive Raman analysis revealed that SSE led to the exfoliation of graphite into multilayered graphene. Furthermore, mechanical property characterization and electrical conductivity (EC) tests conducted on SSE-processed Al-graphene MMC cables demonstrated a favorable synergy between strength and EC. The findings of this study provide a benchmark to understand the SSE capabilities to produce next-generation conductive cables for energy and power sectors.

Keywords

• Al metal matrix composite
• Extrusion
• Graphene
• Raman spectroscopy
• SolidStir Technology
• Strength-conductivity tradeoff