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This research investigates the performance of ABS P400 parts under compressive loading. These ABS P400 parts are fabricated by fused deposition modeling (FDM) process using omnidirectional printing. The effects of three critical parameters, raster angle (A), air gap (B), and raster width (C), each at three different levels, were analyzed on three different performance measures, i.e. total deformation up to failure ($TD$) measured in %, maximum energy ($ME$) in MJ/m³ and break energy ($BE$) in MJ/m³. Results of experimentations were analyzed using analysis of variance (ANOVA), perturbation curve and 3D surface plots. The research established the anisotropic nature, durability and less brittleness of the FDM fabricated ABSP400 part, which leads to lower strength and also influence the energy absorbing behavior while deformation under compression. Complex relationships were exhibited between the chosen parameters and studied measures. It was also observed that $TD$ is noticeable due to less brittleness of ABS P400 however, $TD$ and $BE$ vary in a contradictory fashion with changes in process parameters. The models were validated using normality plots. Multi-objective optimization was done using the desirability approach to determine the optimal combination of FDM process parameters for optimum responses. The desirability result showed that the optimized input parameter is $A=60^{\circ },B=0.002$mm, and $C=0.477$mm which yield maximized optimum responses as $TD=47.94$%, $ME=1.6\times 10^6$MJ/m³, and $BE=2.13\times 10^7$MJ/m³. The work not only reflects the effect of three FDM parameters on the total deformation up to failure ($TD$ in %) but, in addition, energy absorption behavior of FDM parts under compression is also investigated. The study on the behavior of energy at ultimate stress or ultimate load and breaking stress or breaking load were rarely investigated in earlier research which reflects the novelty of our research.

This paper exemplifies the feasibility of expanding a multi-criteria decision-making (MCDM) method to select optimum process parameters during the wire electrical discharge machining (WEDM) of nitinol. The application potential of combined desirability function analysis (DFA) and analytical hierarchy process (AHP) has been reported. Nitinol, a shape memory alloy (SMA), can memorize or retain its original shape when subjected to thermo-mechanical or magnetic loads. Four key input variables, like pulse on time ($T_{\mathrm{\text{ON}}})$, pulse off time ($T_{\mathrm{\text{OFF}}})$, wire tension (WT), and wire feed (WF) have been studied to optimize three correlated responses, like kerf width, material removal rate (MRR), and surface roughness ($R_{\text{a}})$. Process parameter permutations $T_{\mathrm{\text{ON}}}=120\mu$s, $T_{\mathrm{\text{OFF}}}=55\mu$s, $\mathrm{\text{WT}}=8$ kg-F and $\mathrm{\text{WF}}=3$m/min were found to yield the optimum results. For the desired kerf width, MRR and $R_{\text{a}}$, the optimum process parameters were also achieved expending Taguchi’s signal-to-noise ratio. Validation results affirmed that the MCDM approach, AHP–DFA is a proficient strategy to select optimal input parameters for a preferred output eminence for WEDM of nitinol.

Ultrasonic frequency vibration coupled micro-wire electrical discharge machining (UFV-$\mu$ WEDM) has received enormous consideration due to its zero-tolerance machining. Nickel chromium (Ni–Cr) space alloys are a natural choice within the aerospace industry, which are exposed to high temperatures and high pressure, such as turbine seals and exhaust liners. This study reveals the impact of the UFV-$\mu$ WEDM influencing machining parameters like ultrasonic frequency vibration (UFV), servo voltage ($V_S$), time on ($T_{\mathrm{\text{on}}}$), cutting angle ($A_C$), time off ($T_{\mathrm{\text{off}}}$), and current (I) on the Ni–Cr space alloy in terms of minimum surface undulation (Ra) with maximum material removal rate ($M_{\mathrm{\text{RR}}}$). The cutting trials are carried out by central composite design (CCD). Analysis of variance (ANOVA) is used to find out the proportionate contribution of several factors, and it discloses that $V_S$ was the significant parameter impacting Ra (64.57%) and $M_{\mathrm{\text{RR}}}$ (61.86%). The performance sequence of significant influencing parameters is $V_S>T_{\mathrm{\text{off}}}>A_C>T_{\mathrm{\text{on}}}>I$. According to desirability analysis (DA), optimum parameters for numerous solutions are $T_{\mathrm{\text{on}}}=8$$\mu$s, $V_S=50$V, $T_{\mathrm{\text{off}}}=14$$\mu$s, $I=3$A, and $A_C=30^{\circ }$. The optimum conditions lead to the highest $M_{\mathrm{\text{RR}}}$ (5.72mm³/min) and the lowest Ra (3.42$\mu$m). Scanning electron, 3D topography, and atomic force microscope images are used to analyze the machined surface.

This paper describes the pulsed Nd:YAG laser machining characteristics on 6351 aluminum reinforced with silicon carbide (SiC) and boron carbide (B₄C) particles. The composites are prepared using stir casting route by varying the weight percentage of B₄C (0, 5, and 10 wt.%). During experimentation, the traverse speed (5, 15, and 30 mm/s) and the laser pulse frequency (5, 9, and 15 kHz) are considered to evaluate the groove width. The results reveal that the lower pulse frequency produced poor groove surface quality. Higher thermal energy dissipation at lower traverse speed may also result in the formation of recast layer and heat-affected zone. This is evident from the microscopic image and the EDS analysis. Thus, the optimum condition (composite with 10 wt.% B₄C machined at 30 mm/s and 15 kHz) to achieve minimum grove width with improved surface morphology is identified by desirability analysis. Additionally, the regression model is developed to predict future values ($R$² at 91.86% and $R$² (adj) at 87.55%). Finally, the probability plot confirms the effectiveness of the proposed model at 95% confidence level.

This study examines the machinability of hybrid fiber metal laminates (HFML), which are made by nickel–chromium alloy (IN-625) metal-cored carbon (Ca)/aramid (Ar) fiber laminate using ultrasonic vibration-coupled microwire electrical discharge machining (UV-$\mu$WEDM). Since UV-$\mu$WEDM parameters significantly impact the erosion rate ($E_R$) and surface undulation ($S_U$), the main objective was to identify the optimal machining parameters. The input variables include the pulse on ($P_{\text{on}}$), pulse off ($P_{\text{off}}$), current ($I_C$), cutting inclination ($C_I$), and servo voltage ($S_V$) coupled with ultrasonic vibration (UV). The empirical findings show that the servo voltage ($S_V$) significantly impacts $E_R$ (73.93%) and $S_U$ (70.02%). The performance categorization order of significant influencing variable is $S_V>P_{\text{off}}>C_I>P_{\text{on}}>I_C$. The desirability interpretation generated the optimum setting for minimizing $S_U$ and maximizing $E_R$ is $P_{\text{on}}=8\mu$s, $P_{\text{off}}=14\mu$s, $S_V=50$V, $I_C=3$A, and $C_I=30^{\circ }$. Scanning electron microscopic (SEM) images were used to perform the micro-interlayer analysis on the machined surface. Moreover, creating an appropriate HFML is necessary to cut various shapes and sizes to satisfy the demands of diverse applications. 60% of components in the aerospace sector are reportedly rejected in real time due to dimension departure, poor surface finish, and damage found in the final assembly. Investigating the viability of cutting-edge machining techniques like UV-$\mu$WEDM is crucial to minimize damage and improve the quality of HFMLs.