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This study unleashes the potential of nanoporous connected networks as excellent oil reservoirs for reducing friction and wear in Al2O3-Al2O3 tribo-pairs. Alumina were fabricated via slip casting and sintering to generate wide-ranging densifications (70–99.5%) and slid in a reciprocating flat-on-flat configuration. Friction coefficients (FCs) lie between 0.025 and 0.37 which decreased with an increase in normal load (10–220 N), lubricant’s viscosity (19, 289 mPa·s) and sliding frequency (6, 12, 24 Hz). A central finding is that FCs of infused specimens are smaller than those of surface lubricated. Wear rates decreased from 10−5 to

A microgripper is a distinctive instrument used in drug delivery applications. They can ably handle sub-micron objects within the diametrical range 15–25 µm without any damage. A few objects that can be handled using microgrippers include medicinal tablets, capsules and microparticles. The major factors having an influence on the performance of microgrippers include materials utilized, displacement amplification, contact pressure and gripping range. This work is aimed at improving the performance of existing microgrippers keeping in mind their key performance parameters. The existing microgripper used in drug delivery applications is modelled using COMSOL package. It was then analysed to find key parametric values. Also, the modified design of the microgripper was designed keeping in mind the rigidity of the gripper. They were analysed using COMSOL and the best design among the three was selected and compared with existing microgripper model. The modified microgripper model showed enhanced displacement amplification (by 31%), contact pressure (by 28%) and gripping properties. It could be inferred from our experiments that the microgripper made of Si3N4 base material and lead zirconate titanate (PZT) piezo material showed maximum deflection and maximum contact pressure.

Aircraft industries face an undiminished demand for materials with massive strength to weight ratio. Welding and joining are integral processes in any manufacturing industry. High energy–density laser welding and friction stir welding (solid state) (FSW) are established joining techniques for magnesium alloys as they tend to reduce typical effects such as under fill, sag, pores cracks, etc., The research work aims to select aerospace-grade Mg–Zn alloy (ZE41A) for carrying out friction stir welding thereby comprehending the correlation between the friction stir parameters and geometry of the tool with respect to the weld properties. The properties and results obtained from friction stir welding were compared with the properties of laser beam welding carried out previously on the same magnesium alloy of ZE41A. Two traverse and rotational speeds were considered as the governing criterion ultimately giving us four welds. Hardness tests were carried out on the specimens after welding and an interpretation was done in comparison to the laser beam welding results. Uniform hardness distribution was observed in friction stir welded samples and the samples are free from defects ultimately prescribing FSW as a promising welding technique for aerospace applications.

The cutting parameters like cutting speed, feed, and depth of cut can affect the tool life. Also, the vibration of the tool can affect the tool life. The aim of this study is to predict the cutting tool vibration to enhance the tool life. In this paper, vibration of tool is studied with HSS tool (high speed steel) while turning mild steel. The tool vibration is measured using X Viber vibration meter. The experimental data are tabulated and imported to artificial neural network (ANN). A multilayer perceptron model is trained with back-propagation algorithm using the experimental data. The rake angle, cutting speed, and feed are considered as input parameters for training the ANN. The trained ANN is used to predict tool vibration for different conditions. The predicted values are compared for the specific range to justify the tool change.