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An attempt has been made to apply the Taguchi parameter design method and multi-response optimization using desirability analysis for optimizing the cutting conditions (cutting speed, feed rate and depth of cut) on machining forces while finish turning of AISI 4340 steel using developed yttria based zirconia toughened alumina inserts. These zirconia toughened alumina inserts were prepared through wet chemical co-precipitation route followed by powder metallurgy process. The L9(4) orthogonal array of the Taguchi experiment is selected for three major parameters, and based on the mean response and signal-to-noise ratio of measured machining forces, the optimal cutting condition arrived for feed force is A1, B1and C3(cutting speed: 150 m/min, depth of cut: 0.5 mm and feed rate: 0.28 mm/rev) and for thrust and cutting forces is A3, B1and C1(cutting speed: 350 m/min, depth of cut: 0.5 mm and feed rate: 0.18 mm/rev) considering the smaller-the-better approach. Multi-response optimization using desirability function has been applied to minimize each response, that is, machining forces, simultaneously by setting a goal of highest cutting speed and feed rate criteria. From this study, it can be concluded that the optimum parameters can be set at cutting speed of 350 m/min, depth of cut of 0.5 mm and feed rate of 0.25 mm/rev for minimizing the forces with 78% desirability level.

The essence of the “ratio data” in cellular manufacturing system has rarely been correctly emphasized since past few decades of research and study. This article is an attempt to deal with cell formation problem which exploits machine utilization percentage and eliminates the “fuzziness” on the subject of ratio data. In the course of this study, a distinctive technique is adopted based on multi-criteria decision technique with significant modifications which is experimented on test data and compared with published methodology. To verify the grouping result, a novel performance measure is proposed and elaborated analytically to establish its superiority and robustness over the earlier efficiency measures published in the past literature of cellular manufacturing system. The novelty of this research remains in eradicating ambiguities on the subject of “ratio data,” imposing appropriate rules while generating the test problems, catering a unique multi-criteria decision technique–based approach and a novel performance measure for the aforesaid problem.

Microgrooves are one of the basic microfeatures fabricated on different microproducts, used to integrate micro systems in various fields. Service life and product functioning of microproducts are directly influenced by shape, size, and surface quality of microgrooves fabricated on it. Hence, these are the important criteria to be considered while fabricating microgrooves on micro devices. This article presents the experimental study into fabrication of microgrooves on stainless steel by electrochemical micromachining. The influence of electrochemical micromachining process parameters like applied voltage, pulse frequency, duty ratio, electrolyte concentration, and microtool scanning speed on machining accuracy, that is, width overcut, length overcut and depth overcut, material removal rate, linearity of microgroove, depth profile, and surface finish were investigated during microgroove generation. From the experimental results, optimal parameters obtained were applied voltage of 2.6 V, pulse frequency of 8 MHz, 30% duty ratio, electrolyte concentration of 0.15 M H2SO4, and microtool scanning speed of 93.75 μm/s for machining of accurate microgroove, with best surface finish. Finally, microfeatures like “C”-shaped microgroove of rectangular cross section and multiple microgrooves as required in micro thermal devices have been machined with optimal parametric settings. This study will be useful for machining of need-based microgrooves on microproducts like micro actuators, micro pumps, micro coolers, and micromixers.

The electrochemical discharge machining (ECDM) process has become a promising area in the field of non-conventional machining processes, as it has a great potential to machine electrically non-conducting materials such as glass and ceramics. However, when it is applied as a micromachining process, its performance characteristics are influenced by various control factors such as the applied voltage, electrolyte concentration, and interelectrode gap, the characteristics of the power circuit, etc., as a result of variation in the sparking intensity. The objective of the present research work is to find out the most suitable power circuit for the ECDM process during its application in the microdrilling of glass. The influences of various power circuit configurations on the material removal rate (MRR), the tool wear rate (TWR), the radial overcut (ROC), and the heat-affected zone (HAZ) have been investigated using an NaOH salt solution as electrolyte. The individual effects of the inductance L, resistance R, and capacitance Cof the power circuit on machining performance have been studied experimentally in order to find their optimal values. Experiments have been carried out to search for the pairwise effect of power circuit variables by considering their optimal values according to a Taguchi L9orthogonal array. Maximum MRR and minimum TWR can be achieved at LC/60V/20 wt %/20 mm and RL/50 V/30 wt %/40 mm respectively. Minimum ROC and minimum HAZ thickness have been obtained at RC/50 V/10 wt %/40 mm. Thus, from the point of view of the accuracy and quality of the machined hole, an RC circuit has been found to be most suitable for the micromachining of electrically non-conducting materials by the electrochemical discharge machining process.