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Both AFM imaging and stress measurements were carried out in-situ during potentiostatic electrodeposition of copper on gold in 0.05 mol dm-3 CuSO4 in 0.1 mol dm-3 H2SO4. In the absence of additives, compressive stress generally developed initially and films subsequently underwent a compressive-to-tensile (C-T) transition. The nucleation density measured by AFM increased from 2.7x107 cm-2 at -75 mV to 2.5x109 cm-2 at -300 mV. Very little coalescence of nuclei was observed at -75 mV but the rate of coalescence increased rapidly with increasing negative potential. The time for the C-T transition correspondingly decreased rapidly until, at -75 mV, none was observed. This is consistent with models that attribute the C-T transition to increasing tensile stress due to coalescence of nuclei. With a combination of Cl-, PEG and MPSA, compressive stress generally developed initially and was greater than in additive-free electrolyte. At less negative potentials, the stress continued to evolve in the compressive direction, even though the rate of coalescence of nuclei was rapid. At intermediate potentials (-90 mV to -150 mV), classical C-T-C behavior was observed; at more negative potentials the stress continued to evolve in the tensile direction. This enhancement of a compressive component of stress is attributed to incorporation of additive-derived impurities.

Powder metallurgy (P/M) manufacturing process is one of the rapidly emerging fields and has extended the applications in aerospace, automotive, manufacturing industries replacing all traditional methods of metal forming operations because of its less energy consumption, maximum material utilization, low relative material wastage, low capital cost. The mechanical properties is mainly depends on the final density of sintered P/M alloys. The typical microstructure characteristics of sintered steel represent an important parameter affecting their wear behaviour. The present research work pertains to the study of dry sliding wear characteristics of sintered P/M Fe-1%C-1%W-1%Ti low alloy steel with different densities (85%, 90%, 95%), as they find several applications in manufacturing industries, particularly in automobile industries. These components usually face workingconditions involving abrasion, rolling and sliding, making it important to study the wear phenomenon. The wear behavior of the as-sintered preforms were studied under dry conditions on pin-on disc arrangement (ASTM G99) against EN 38 steel disc of Hardness HRC 60 with a sliding speed of 2 m/s and at a normal loads of 30, 50, 70N respectively. Wear mechanism of the worn out surfaces and microstructure of sintered P/M alloy steel has been characterized using both optical microscopy and SEM. Ferritic-pearlite microstructure are revealed from the as-sintered P/M alloy steels. Wear rate increases gradually with increase in porosity with respect to applied load. The main wear mechanism in the Ti alloyed P/M steel seems to be delamination wear in the higher load and oxidation wear at lower load. Failure by a delamination process is clearly indicated by the shape of the debris particles.

A B S T R A C TThis paper reviews the energy harvesting for micro level devices such as mobile phones, low powered signal lights and energy storage batteries by using Lead Zirconite Titanite (PZT) with the help of vibration on cantilever beams and batteries. Recent advances on micro power portable devices require limitless battery life for improving performance. A lot of energy is being wasted which is around us and also research has been conducted to develop energy harvesting devices by using PZT materials. This paper gives innovative ideas to develop energy harvesting devices for future scientific community.