Gas/plasma cutting of cladded materials provides inferior cut quality that demands subsequent finishing processes. Abrasive waterjet cutting could be a proficient alternate in terms of cut quality. However, the inherent problem of kerf taper and low material removal rate in comparison to the said thermal cutting processes limit its application. Therefore, potential of aforesaid machining process for cutting of stainless-clad steel is investigated with a prior focus on maximizing the material removal rate with minimum kerf taper. Abrasive mass flow, traverse speed, water pressure, and stand-off distance have been selected as input parameters. ANOVA analysis revealed that traverse rate as well as abrasive mass flow are the major contributing factors for both the responses. Optimal settings of parameters developed by S/N ratio analysis results in an improvement of 18.6% in material removal rate and 39% in the kerf taper. Moreover, regression models are developed and validated through various statistical tests.

Al-matrix composites specifically Al6061-7.5%SiC which holds promising mechanical properties, is a potential candidate in aeronautical industry. Though the reinforcement of SiC in Al-substrate has appreciably enhanced the mechanical characteristics, but it complicates its machining as the composite bears excellent hardness and strength. Moreover, its intended applications require the formation of intricate profiles. Therefore, the processing/machining of such composite is challenging. Wire electric discharge machining (WEDM) is an appreciable choice for Al6061-7.5%SiC machining. However, intrinsic issues of WEDM, i.e., wire vibrations and lag have resulted in a compromised dimensional accuracy of machined part. Furthermore, realization of similar errors’ magnitude in both the cutting orientations (axial; E_XD and lateral; E_YD) is difficult because of the presence of SiC-reinforcement which is a stimulus for wire disturbances. Similarly, this reinforcement influences corner accuracy and makes it’s tedious to attain same corner errors at both faces (top; AE_TOP and bottom; AE_BOT). These accuracy issues have not been discussed yet which is primarily done herein using response surface methodology. Statistical, optical, and SEM analyses are performed for detailed understanding of the parametric effects. The minimum error values achieved are 0.01 mm, 0.105 mm, 0.249° and 0.475° in case of E_XD, E_YD, AE_TOP and AE_BOT respectively.

Inconel 617 has unique characteristics however it is extremely difficult to machine this alloy with conventional processes. Thereof, generally electric discharge cutting (EDM) is engaged for its precise cutting. The intrinsic issue of low machining rate in EDM confines its application. Therefore, this problem has been comprehensively examined herein employing different cryogenically treated electrodes, which has not been targeted so far. Moreover, the potentiality of modified dielectrics in the aforementioned context using the both cryogenic treated and non-treated electrodes have also been investigated. Experimentation was performed using three types of electrodes against five types of dielectric media under full factorial design. Total 30 experiments were performed. The electrode of Cu has outperformed in terms of material removal rate (MRR) in both treated and non-treated forms. The highest magnitude of MRR (15.66 mm³/min) has been achieved using a blend of Span-20 and kerosene dielectric. Cryo-trated brass has provided 95.2% higher MRR than that obtained with non-deep cryogenic treated (non-DCT) brass using kerosene as dielectric. Cryo-treated graphite tool produced the largest MRR (4.6 mm³/min) when T-20 mixed kerosene is used. Span-20 added kerosene is the best choice for getting high MRR if non-DCT electrodes are used whereas Tween-20 mixed kerosene is best suited for cryo-treated electrodes.

Squeeze overcasting has emerged as an attractive option for casting of Al alloys in terms of mechanical properties. The attainment of the desired magnitude of these properties is challenging in overcasting due to the involvement of a number of process parameters. In this study, the effects of insert preheat temperature (T_I) along with pouring temperature (T_P), and squeeze pressure (P_S) on the mechanical properties of squeeze overcast AA2026-AA2026 joint were investigated. Experimental results revealed that the squeeze pressure is the most prominent factor affecting the ultimate tensile strength (UTS) while micro-hardness (MH) is significantly influenced by the pouring temperature. Maximum values of UTS (315 MPa) and MH (130 HV) were achieved at aP_Sof 120 MPa,T_Pof 780 °C, andT_Iof 250 °C. Energy dispersive X-ray (EDX) analysis witnessed thatT_Ihas also a significant role in determining the quality of bond between the substrate and the melt. Scanning electron microscopy (SEM) depicts that the morphology of the fractured surface has a sound influence on both selected responses. Both the strength and hardness are noticed better if the fractured surface possesses the flat-faced morphology. Furthermore, an empirical regression model was developed using response surface methodology (RSM) design and validated through eight confirmatory experiments. RSM integrated multi-objective optimization genetic algorithm (MO-GA) was deployed to optimize the UTS and MH. The comparative results obtained from RSM and MO-GA demonstrated that the deviation in experimental and predicted values is less than 5%.