Articles written in Bulletin of Materials Science
Volume 42 Issue 5 October 2019 Article ID 0204
Effect of exfoliated few-layered graphene on corrosion and mechanical behaviour of the graphitized Al–SiC surface composite fabricated by FSP
ABHISHEK SHARMA VYAS MANI SHARMA BAIDEHISH SAHOO JOMY JOSEPH JINU PAUL
The inﬂuence of friction stir processing parameters and the subsequent evolution of microstructures and cor-rosion behaviour of Al–SiC surface composites fabricated in the presence of graphitic ﬂakes are presented in this paper. The circumferential shear stress exerted by the rotating tool exfoliates the graphite ﬂakes into few-layered graphene during processing. These graphene ﬂakes preferentially occupy both the grain boundaries and the SiC–Al interface during recrys-tallization. The potentiodynamic polarization test, in 3.5 wt% sodium chloride (NaCl) solution, is conducted for samples processed at various tool rotational speeds and it is found that the presence of this thin graphitic layer at these locations reduces the intergranular and interfacial corrosion to a great extent. The tool rotational speed has a signiﬁcant inﬂuence on processing, and samples fabricated at an optimum tool rotational speed of 2200 rpm shows better corrosion resistance and mechanical properties as compared to that at lower and higher speeds. Raman spectroscopic analysis, X-ray diffraction studies and microhardness tests corroborate the experimental results and the proposed mechanisms.
Volume 45 All articles Published: 28 February 2022 Article ID 0044
Electromagnetic shielding efficiency of carbon fibre fabric-sandwiched epoxy–MWCNT nanocomposites
ABHISHEK SHARMA MYNENI SUKESH BABU ASAPU VINAYA KUMAR R SARATHI V SUBRAMANIAN
The impact of reinforcing multi-walled carbon nanotubes (MWCNT) and uni-directional carbon fibre fabric (UCFF) in the epoxy polymer matrix on the electromagnetic interference shielding efficiency (EMI SE) is studied in the X-band frequency range (8–12 GHz). The increase in the weight percentage (wt%) of pristine MWCNT increases the EMI SE of the nanocomposites. Inclusion of UCFF, as a layer, enhances the EMI SE of the structure to a great extent giving an EMI SE of around 75 dB at 12 GHz for UCFF-sandwiched 5 wt% MWCNT–epoxy composite. The layered structure, epoxy–MWCNT/UCFF/epoxy–MWCNT introduces heterogeneity and this results in a SE much higher than the individual contributions of MWCNT and UCFF. The analysis suggests that the presence of thin layer of UCFF absorbs the radiation apart from inducing multiple scattering enhancing the absorption within the MWCNT– epoxy region.
Volume 46, 2023
Continuous Article Publishing mode
Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
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