Fatmah Alsalami , Ian A. Kinloch , Rashid K. Abu Al-Rub , Cristina Vallés
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引用次数: 0
Abstract
The potential of electrically conductive polycarbonate (PC) nanocomposites filled with carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) as heating elements to Joule weld PC substrates was investigated. Both GNPs/PC and CNTs/PC nanocomposites behaved as electrically percolated systems, with the CNTs rendering higher conductivities at considerably lower concentrations. Maximum values of 10.57 S/m and 0.028 S/m were achieved for the nanocomposite filled with 10 wt% loading of CNTs and 15 wt% loading of GNPs, respectively. The incorporation of 5 and 10 wt% loadings of CNTs into the polymer seemed to favour the development of denser conductive networks, capable of achieving the temperature required for an effective Joule welding of PC substrates under an applied voltage, whereas the addition of lower loadings of CNTs (i.e., ≤5 wt%) or GNPs at any loading ≤10 wt% rendered less conductive networks, not capable of achieving a high enough temperature for a successful Joule welding. The samples welded with the nanocomposite filled with 10 wt% CNTs showed higher lap shear strength (LSS) values (13.1–14.1 MPa) than those welded with the nanocomposite containing 5 wt% CNTs (12.3–12.9 MPa) due to the higher filler loading providing a higher conductivity and a more homogeneous Joule heating all throughout the heating element under the applied voltage. Likewise, increasing welding times, pressures and clamping distances led to progressively higher LSS of the Joule welded joints up to optimal values, with optimal times of 120 and 150 s being found for the nanocomposites containing 10 and 5 wt% loading of CNTs, respectively, and optimal pressure and clamping distance values of 1 MPa and 1.2 mm, respectively, being observed for both of them. This work demonstrates the potential of electrically conductive CNTs based polymer nanocomposites as heating elements for thermoplastics Joule welding, and highlights their formulation, applied voltage and welding parameters, including time, pressure and clamping distance, as key factors that can be strategically tuned to control the welding process and optimize the joints’ mechanical performance.
期刊介绍:
Composites Part B: Engineering is a journal that publishes impactful research of high quality on composite materials. This research is supported by fundamental mechanics and materials science and engineering approaches. The targeted research can cover a wide range of length scales, ranging from nano to micro and meso, and even to the full product and structure level. The journal specifically focuses on engineering applications that involve high performance composites. These applications can range from low volume and high cost to high volume and low cost composite development.
The main goal of the journal is to provide a platform for the prompt publication of original and high quality research. The emphasis is on design, development, modeling, validation, and manufacturing of engineering details and concepts. The journal welcomes both basic research papers and proposals for review articles. Authors are encouraged to address challenges across various application areas. These areas include, but are not limited to, aerospace, automotive, and other surface transportation. The journal also covers energy-related applications, with a focus on renewable energy. Other application areas include infrastructure, off-shore and maritime projects, health care technology, and recreational products.