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The intent of the proposed research is to analyze the effect of Silicon Nitride (Si3N4) and synthesized Graphene Oxide (GO) on the physical, wear and corrosive characteristics of the copper. The copper hybrid composite having constant GO and varying weight % of Si3N4 is prepared through powder metallurgy. The GO is synthesized from graphite through modified hummers method and its formation is confirmed through SEM, XRD, Raman and FTIR analysis. The SEM analysis of developed Cu/0.3rGO/xSi3N4 confirms the presence of reinforcements and density analysis confirms the reduction density. The microhardness is found increasing with GO and Si3N4 addition. Wear rate of the copper found decreases with reinforcement addition due to self-lubricating nature of GO and hardness of Si3N4 ceramic. Worn surface confirms the transition of severe wear to mild wear with Si3N4 addition. The corrosion results suggest that the composite reinforced with 0.3% GO and 15% Si3N4 yielded better corrosion resistance than the other developed composites. Corroded surface analysis confirms the reduction in surface damage with reinforcement addition that shows increase in corrosion resistance of copper with hybrid reinforcement addition. [ABSTRACT FROM AUTHOR]

The objective of the current research is to analyse the feasibility of utilising welding slag as flux material in Submerged Arc Welding (SAW) of A36 steel. The amount of welding slag incorporated with virgin flux is varied from 20 to 50 percent in weight at an equal interval of 10%. The material welded with virgin flux and slag mixture of different proportion is tested for hardness, tensile and impact properties along with its soundness through radiography and ultrasonic testing. Hardness, tensile, yield and impact strength of the weld decreases with incremental inclusion of slag in SAW flux. Up to 30% slag additions provide optimum results where as 40 and 50% slag addition causes detrimental weld quality. Radiography and ultrasonic testing confirms the defect free weld samples welded with less slag addition, whereas welds performed with higher slag addition possess internal defects. Based on the weld quality and cost of weld materials, it is suggested to use waste slag up to 20–30 wt % with SAW flux wherein any deviation from this level will deteriorate either quality or profitability. The study favours usage of slag in the flux and contributes for reduction in the overall slag generation.

The aim of this experimental work is to find the ideal wire electric discharge machining (WEDM) parameter combination for processing a novel FeCoCrNiMn High Entropy Alloy (HEA)-reinforced magnesium composite. This composite is developed with varying weights of FeCoCrNiMn at 5%, 10%, and 15% through powder metallurgy. Experiments are performed to examine the effects of HEA and wire-EDM variables on surface roughness (Ra) and kerf width (KW) using Taguchi's L27 orthogonal array. The hybrid ENTROPY-COCOSO (Combined Compromise Solution) methodology is used for multiple objective optimizations after the Taguchi method for optimization. The most significant constraints on Ra and KW are found to be pulse ON time and current. Wider kerfs and rougher surfaces are the result of longer pulse ON times and higher current. The ideal input parameters recommended by ENTROPY-COCOSO for minimal Ra and KW are 2 A of current, 20 µs of pulse ON time, 25 µs of pulse OFF time, and 4 mm/min of wire feed rate. To predict outcomes, both linear regression models and artificial neural networks (ANNs) are used, and the results are compared with experimental data. The results are validated by the fact that ANN predictions closely match experimental data with minimal deviation. [ABSTRACT FROM AUTHOR]

In this work, a newly discovered biomedical grade Magnesium–Lithium–Strontium (Mg–Li–Sr) alloy is machined using electrochemical machining technology. Two main output constraints employed on the research project to evaluate machinability are surface roughness (Ra) and material removal rate (MRR). Changing feed rate (FR), current, electrolyte concentration (EC), and voltage is required in order to carry out experimental experiments. The trials were designed using the Taguchi method. The ANOVA findings show that current is the most significant factor, after voltage as the most significant input parameter in regulating Ra and MRR. The ideal parameter configuration for the CRITIC-linked Deng's similarity approach method was 5 V, 1 A of current, 0.4 mm/min of FR, and 20 g/l of EC. The final product was a 0.0323 mm/min MRR and a 2.61 μm surface roughness. Furthermore, the response variables are anticipated using the adaptive neuro-fuzzy Inference System, which finally results in predictions that are very similar to the experimental results. [ABSTRACT FROM AUTHOR]

The present research examines the impact of Si3N4–BN hybrid reinforcement on the machinability of a magnesium hybrid composite in wire electrical discharge machine (WEDM). The composite is fabricated through inert gas assisted stir casting route with silicon nitride and boron nitride as reinforcement with varying weight percentages of 0%, 5%, and 10%. Subsequently, the fabricated composites were machined through WEDM according to Taguchi 27 orthogonal array with varying pulse on time (PON), pulse off time (POFF), wire feed rate (WFR), and wire tension (WT). The machinability of the composite was evaluated by measuring Surface Roughness (SR), Kerf Width (KW), and Cutting Velocity (CV) during WEDM. Results reveals that the % of Si3N4 has greater influence over kerf width and cutting velocity whereas BN % has higher influence over surface roughness. The optimization of process parameters using the Taguchi method resulted in different combinations of parameters for each output response. Therefore, Grey Relational Analysis was applied to determine the common optimal process parameters for all three considered output responses. The identified input parameters that yielded the higher CV, minimal SR and KW were as follows: 0% Si3N4 and BN, 6 µs PON, 14 µs POFF, 6 m/min WFR, and 10 g WT. Artificial Neural Network model has been developed to predict the output response CV, SR and KW. The 6–8–3 network model predicts the output responses with better accuracy with overall R2 value of 99.3%. [ABSTRACT FROM AUTHOR]

Abrupt advancement in technologies lead to growing thirst for efficient and economical alternative materials that possess superior properties. This lead to a gradual shift from the use of monolithic alloys to Metal Matrix Composites (MMCs). High resistance to corrosion and wear makes Aluminium MMC (AMMC) the most promising variant for structural, automotive, marine and aerospace applications. This review opens an insight into the current advancement of AMMCs, detailing an overview on diverse matrices and types of reinforcements that were used to produce such composites. This work also explores and classifies the gain and shortcomings of various phase formations during thermal treatment, revealing the possibilities of improving the physical strength and wear resistance with minimal complexity. This work also highlights the growing concern on corrosion performance of advance AMMC with ceramic reinforcements. In spite of the challenges involved in commercialising AMMC, recent trends of industrial utility reveal their potential to meet evolving demands. [ABSTRACT FROM AUTHOR]

The present study aims to develop a novel hybrid polymer composite with reduced graphene oxide (rGO) as filler and optimize its Abrasive Water Jet Machining (AWJM) parameters for reduced kerf width. The influence of rGO addition on kerf width is analysed in detail along with Pump pressure (bar), Transverse speed (mm/min) and Standoff distance(mm). The experiments are designed based on Taguchi's orthogonal array techniques in which L27 is adopted for three input parameters at three levels. The influence of each factor is used to identify the significance of selected parameters over kerf width, and it was found that stand of distance has a major effect over kerf width irrespective of rGO %. The addition of rGO filler has a significant effect on kerf width, which decreases with the addition of rGO up to 0.2% and kerf width increases for further addition of rGO.