Product Code: ICA12_P135

Incorporation of CNT-Yarns into Metals by Laser Melting of Powder
Authors:
Alexander Kaplan, Luleå Univ. of Technology; Lulea Sweden
Alexander Soldatov, Luleå Univ. of Technology; Lulea Sweden
Maxime Noel, Luleå Univ. of Technology; -
Peter Norman, Luleå Univ. of Technology, The Swedish Welding Commission; Stockholm Sweden
Ingemar Eriksson, Luleå Univ. of Technology; -
John Powell, Luleå Univ. of Technology, Laser Expertise Ltd.; Nottingham Great Britain
Shaoli Fang, Univ. of Texas at Dallas; Dallas TX USA
Ray Baughman, Univ. of Texas at Dallas; Dallas TX USA
Presented at ICALEO 2012

Carbon Nanotubes, CNTs, have extraordinary properties and they can be spun into several meter long yarns with a diameter of the order of micrometer, and even be woven into fabrics. By embedding CNT-yarns or CNT-fabrics into metals, a new kind of composite material could be achieved that would enables the modification of the mechanical properties of a product along a designed path or domain. This paper discusses a preliminary experiment in which CNT-yarns and CNT-fabrics were successfully embedded between a steel substrate and a preplaced metal powder that was melted with an Yb:fibre laser. Suitable parameters were identified. The wire shape remained, i.e. the carbon did not dissolve or evaporate, but remained in the metal matrix. Ti-sputtering of the CNT-yarns prior to welding was advantageous for wetting and embedding. Certain powder materials such as Co-base alloy or Al-bronze turned out to be advantageous to the process. Raman spectroscopy has shown that the CNT-structure is lost for CNT-yarns too close to the molten zone. Further studies are needed, particularly mechanical testing to understand the interaction and reinforcement potential of CNT-yarn in a metal matrix under load. Preliminary bending tests and Finite Element Analysis have shown promise. Creative design solutions can be expected.