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With the enhancement in science and technology, necessity of complex shapes in manufacturing industries have become essential for more versatile applications. This leads to the demand for lightweight and durable materials for applications in aerospace, defense, automotive, as well as sports and thermal management. Wire electric discharge machining (WEDM) is an extensively utilized process that is used for the exact and indented shaped components of all materials that are electrically conductive. This technique is suitable in practically all industrial sectors owing to its widespread application. The present investigation explores WEDM for LM6/fly ash composites to optimize different process variables for attaining performance measures in terms of maximum material removal rate (MRR) and minimum surface roughness (SR). Taguchi’s L27 OA design of experiments, grey relational analysis, and analysis of variance (ANOVA) were employed to optimize SR and MRR. It has been noted from ANOVA that reinforcement (R) percentage and pulse on time are the most influential aspects for Grey Relational Grade (GRG) with their contributions of 28.22 and 18.18%, respectively. It is found that the best process variables for achieving the highest MRR and lowest SR simultaneously during the machining of the composite are gap voltage of 30 V, pulse on time of 10 µs, pulse off time of 2 µs, wire feed of 8 m/min, and R of 9%. The predicted GRG is 0.84, and the experimental GRG value is 0.86. The validation experiments at the optimized setting show close agreement between predicted and experimental values. The morphological study by optical microscopy revealed a homogenous distribution of reinforcement in the matrix which enhances the composite’s hardness and decreases the density.

NAO brake friction materials with 4%, 5%, and 6% (w/v) sodium hydroxide treated hemp fiber reinforcement having 25% wt. fiber loading and fixed percentage of phenol formaldehyde resin content (20% wt.) along with other fillers have been studied and reported by the authors earlier. However, the effect of variations in the resin content on the tribological performance has been studied and reported in the present paper. Five variants were prepared with varying percentages of phenol formaldehyde resin from 12% wt. to 22% wt. with incremental steps of 2% wt, along with the optimum of 6% (w/v) sodium hydroxide treated hemp fibers and other fillers. The prepared test variants' tribological characterization was done using Taguchi's L25 orthogonal array on a pin-on-disc experimental setup, as per ASTM G99, at room temperature and compared with the best of the earlier studied friction composite. Fade and recovery tests of the best of the earlier studied and present ones were performed on a chase tribology tester per SAE J661 standards. The results revealed moderate coefficient of friction of 0.4496, lower wear rate of 0.57 gm, and better fade recovery for the HF25P20 variant compared to its counterparts studied here. [ABSTRACT FROM AUTHOR]

The materials used in engineering have seen a significant transformation in the contemporary world. Numerous composites are employed to overcome these problems because conventional materials are unable to meet the needs of current applications. For quite some time, professional engineers and researchers have been captivated by the problem of choosing the best machining parameters for new composite materials. Wire electrical discharge machining is a popular unconventional machining process that is often used for making complex shapes. Numerous process parameters influence the WEDM process. Thus, to achieve affordable and high-quality machining, the right set of process parameters must be provided. Finding the wire cut EDM optimized settings for the fabricated LM5/ZrO2/Gr composite is the main aim of this research. The chosen input parameters are the wire feed, pulse on and pulse off times, the gap voltage, and the reinforcing percentage. In this study, LM5/ZrO2/Gr composites were made from stir casting with 6-weight percent ZrO2 as the reinforcement and varying graphite percentages of 2, 3, and 4 wt%. Then they were machined in WEDM using L27 OA to seek the best parameters for machining by adjusting the input parameters. The findings were analysed by means of grey relation analysis (GRA) to achieve the supreme material removal rate (MRR), lowest surface roughness (SR), and a smaller kerf width (Kw) simultaneously. GRA determines the impact of the machining variables on the standard characteristics and tests the impact of the machining parameters. Confirmation experiments were performed finally to acquire the best findings. The experimental findings and GRA show that the ideal process conditions for achieving the highest grey relational grade (GRG) are 6% ZrO2 with 2% graphite reinforcement, a wire feed of 6 m/min, a pulse off time (Toff) of 40 µs, a pulse on time (Ton) of 110 µs, and a gap voltage (GV) of 20 V. The gap voltage (22.87%) has the greatest impact on the GRG according to analysis of variance (ANOVA), subsequent to the interaction between the pulse on time and the gap voltage (16.73%), pulse on time (15.28%), and pulse off time (14.42%). The predicted value of the GRG is 0.679; however, the experimental GRG value is 0.672. The values are well-aligned between the expected and the experimental results. The error is only 3.29%, which is really little. Finally, mathematical models were created for each response. [ABSTRACT FROM AUTHOR]

The endodontic file is a tapered, needle shape body used for the preparation of curved human root canals. During the preparation, process files get failed due to the locking action offered by the canal wall. The present study aimed to find the fatigue life of endodontic files at 23°, 33° and 43° root canal curvature angles. Four brands of files were selected for the present study viz. Hyplex CM, Pro-Taper Next, Hero Shaper, Pro-File Vortex. The strain life analysis done using ANSYS showed that the Hyplex CM file gives the highest fatigue life at 23°, 33° and 43° root canal curvature angles. Therefore, Hyplex CM file was selected for DoE Taguchi Optimization study. Each experimental reading was conducted on X Smart Plus experimental setup under purely rotary and combined reciprocating-rotary motion, at 500 rpm, 600 rpm and 700 rpm and 23°, 33° and 43° root canal curvature angles. Hyplex CM file given maximum fatigue life at 23° root canal curvature angle and 500 rpm speed of rotation. But if file motion is combined rotary-reciprocating, life reduces. The ANNOVA study showed that P-value and significance F are very small, which represented that the regression model is effective.

Fabrication of electronic circuits and the effects of optimization parameters on electrical conductivity of the printed circuits fabricated by direct ink writing method (D.I.W); one of the novel methods in 3D printing technologies is discussed in this work. This paper focuses on fabrication of electronic circuits using F-MWCNT/PVA conductive ink and analyses the effect of input printing process parameters namely nozzle diameter, extrusion pressure, printing speed on evaluating the electrical conductivity. Box–Behnken approach is followed to generate the levels of experiments and the performance of developed model is assessed using ANOVA. Response surface method is incorporated to find the influencing parameters on electrical conductivity response. Two-point probe measurement method is performed to analyse the output response of the printed electronic circuits. Optimized printing parameters such as nozzle diameter of 0.8 mm, extrusion pressure of 0.1 MPa and printing speed of 4 mm/sec are found to be the best the for printing electronic circuits with high electrical conductivity. [ABSTRACT FROM AUTHOR]