Bankim Chandra Ray

An assessment of flexural performance of liquid nitrogen conditioned glass/epoxy composites with multiwalled carbon nanotube

The objective of the present investigation is to study the alteration in flexural performance of glass/epoxy (GE) composite with and without multiwalled carbon nanotube (MWCNT) after liquid nitrogen conditioning. The epoxy resin was first modified by 0.1, 0.3, and 0.5u2009wt% MWCNT, which was then used along with E-glass fibers to fabricate laminates. Flexural strength and modulus were evaluated by 3-point bend test. Out of these four compositions, the maximum strength in the as-fabricated condition was obtained for GE composite with 0.1u2009wt% CNT, which is 32.74% higher as compared to GE composite. Decrease in strength and modulus was observed for short time span of liquid nitrogen conditioning i.e. 0.25u2009h. Long cryogenic conditioning resulted in increment in strength. To understand the failure mechanisms, post failure analysis was carried out using scanning electron microscope. The design parameters are calculated using Weibull distribution model.

On the effects of bath composition and ultrasound on structure and properties of Cu thin films

Copper thin films were prepared by sono-electrodeposition method at different acid concentrations in the electrolyte. A potential of −450 mV (100 mV negative than the Nernst potential) was selected for the deposition procedure for all the conditions. The thickness of films was found to be in the range of 100–600 nm. Electrochemical analysis was performed by chronoamperometry. Films were characterized by XRD, SEM, AFM, and study of the mechanical properties was done by nanoindentation.

Implication of low temperature and sonication on electrocrystallization mechanism of Cu thin films: a kinetics and structural correlation

The effect of an ultrasonic environment during electrodeposition of copper on graphite at various electrolyte temperatures of 25, 20, 15, 10 and 5 °C is reported in this investigation. Resulting Cu deposits formed by potentiostatic deposition were characterized by electrochemical methods, scanning electron microscopy and atomic force microscopy. It was found that in presence of ultrasound the deposition kinetics was mainly dominated by the charge transfer. Copper nucleated according to 3D instantaneous mechanisms for all temperature ranges. The extent of nucleation was found to be increased at low temperatures. Diffusion coefficients and nuclei population density were calculated for each temperature range. Sonicated deposits with good surface coverage were found to consist of spherical copper agglomerates of nanosized particles.