Abstract Flexible nanocomposite films, with cobalt ferrite nanoparticles (CFN) as the ferromagnetic component and polyvinylidene fluoride–trifluoroethylene (PVDF-TrFE) copolymer as the ferroelectric matrix, were fabricated using a blade coating technique. Nanocomposite films were prepared using a two-step process; the first process involves the synthesis of cobalt ferrite (CoFe2O4) nanoparticles using a sonochemical method, and then incorporation of various weight percentages (0, 2.5, 5, and 10%) of cobalt ferrite nanoparticles into the PVDF-TrFE to form nanocomposites. The ferroelectric polarβphase of PVDF-TrFE was confirmed by x-ray diffraction (XRD). Thermal studies of films showed notable improvement in the thermal properties of the nanocomposite films with the incorporation of nanoparticles. The ferroelectric properties of the pure polymer/composite films were studied, showing a significant improvement of maximum polarization upon 5wt% CFN loading in PVDF-TrFE composite films compared to the PVDF-TrFE film. The magnetic properties of as-synthesized CFN and the polymer nanocomposites were studied, showing a magnetic saturation of 53.7 emu g−1at room temperature, while 10% cobalt ferrite-(PVDF-TrFE) nanocomposite shows 27.6 emu/g. We also describe a process for fabricating high optical quality pure PVDF-TrFE and pinhole-free nanocomposite films. Finally, the mechanical studies revealed that the mechanical strength of the films increases up to 5 wt% loading of the nanoparticles in the copolymer matrix and then decreases. This signifies that the obtained films could be suited for flexible electronics.
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Fabrication of High Strength Al Nanocomposites with Populous TiB2 Nanoparticles
High performance lightweight metals offer tremendous potential to improve energy efficiency and system performance for numerous applications. Traditional manufacturing processes such as thermomechanical processing and deformation have reached their limits in further improving the properties of metals. Thus, a new approach is necessary to develop high performance lightweight metals which can offer promising properties. Metal matrix nanocomposite (MMNC) is an excellent approach to produce lightweight metals with improved properties that cannot be achieved by traditional manufacturing. Effective incorporation of a suitable nanoparticles system in a metallic matrix such as aluminum (Al) can improve the performance of the matrix. However, due to the high chemical reactivity and poor wettability of Al with nanoparticles, achieving high volume fraction of nanoparticles incorporation is of a great challenge. Here we show a novel approach to incorporate high volume fraction of titanium diboride (TiB2) nanoparticles in Al matrix. Al-TiB2 nanocomposite microparticles were initially produced via flux assisted solidification processes. Al-TiB2 nanocomposites were produced by cold compaction followed by melting. Scanning electron microscopic (SEM) images revealed that the TiB2 nanoparticles are unfirmly dispersed and distributed in Al matrix. Al-TiB2 nanocomposites with as high as 485.9±16.9 Vickers hardness were successfully produced. Furthermore, the effect of melting time was studied on the hardness of the Al-TiB2 nanocomposites.
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- Award ID(s):
- 1639164
- PAR ID:
- 10077202
- Date Published:
- Journal Name:
- Procedia manufacturing
- Volume:
- 26
- ISSN:
- 2351-9789
- Page Range / eLocation ID:
- 629-632
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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