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Doping in lead-zirconate-titanate (PZT) thin films is on the rise for next generation micro-electromechanical systems (MEMS) and energy harvesting applications, owing to their improved ferroelectric and piezoelectric properties. Strontium, lanthanum and neodymium like elements are the most exploited for such applications. This paper reports realization of a PZT thin film with strontium and lanthanum co-doping in tandem, Pb 1−x−3y/2 Sr x La y (Zr 0.56 Ti 0.44 )O 3 x=0.06, y=0.03 (PSLZT), by RF sputtering process. Different process conditions like substrate temperature from 250°C-350°C and annealing temperature from 650°C-750°C are studied to achieve pyrochlore free PSLZT thin film. The structure, surface morphology, surface topography and ferroelectric characteristics are investigated using x-ray diffraction (XRD), Atomic Force Microscopy (AFM), Field Emission Scanning Electron Microscopy (FE-SEM) and P-E analyser, respectively. Nanoscale polarization switching processes and the local surface displacements are studied to ascertain that the PSLZT thin film exhibits the ferroelectric and piezoelectric properties. Experimental results reveal that the present PSLZT thin film has a polarization of 5.5 μC cm −2 , leakage current density of 10 −5 A cm −2 and piezoelectric charge coefficient, d 33 , of 87 pm V −1 , which are suitable for realization of various new piezoelectric MEMS sensors.

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Al–Si–Cu alloy oil pump casings used in heavy automotive were produced through gravity die casting process. The customer requirement of 80–125 BHN with a ductility of 3% was not attainable with gravity die casting process. To acquire required level of ductility and hardness, heat treatment process was applied as post-processing, which increases the production cost and time. The squeeze casting technique is a process suitable to enhance the mechanical properties. A set of experiments was designed based on Box-Behnken method of Response Surface Methodology (RSM) to find the optimal parameter settings for squeeze casting process. Squeezing pressure, pouring temperature and dwelling time were considered as process parameters and a model for the process was created. Analysis of variance (ANOVA) results revealed that the model created is acceptable. Excel Solver was used to determine the optimal parameter settings to obtain maximum ductility and hardness. Confirmation tests were carried out to validate settings. The squeeze casting process, with the recommended settings, enhanced the mechanical properties and the heat treatment operation was eliminated.

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