Al6063 composites are widely used in automobile, aerospace and biomedical industries due to their excellent mechanical properties. Machining of micro channels in composites is difficult for conventional machining process due to presence of hard reinforcement. Materials with base metal. Micro Electrical discharge (µED) milling is popular micromachining technique for machining simple, intricate shapes and microchannels on any conductive material. However, it a slow machining process, the identification of optimum condition has become wide research area in µEDM. The present work aims to study the influence of process variables namely voltage, spindle speed and threshold on machining characteristics of µED milling of Hybrid Metal Matrix Composites (HMMCs). Experimental trials are carried out with copper electrode at different parametric condition. Al6063-5%B4C-5%ZrSiO4 composite was fabricated using stir casting method and experimental runs were designed using general full factorial method. The significant parameters are identified using Analysis of Variance (ANOVA) and the ideal machining conditions for multi-response are determined using Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method. The morphology of machined surface with best and worst conditions is examined using SEM. Results indicated that the voltage and threshold are the influencing parameters for considered response indicators. Recast layer thickness seems to be low with best machining conditions as compared to worst conditions. Increase in voltage and threshold increases the Material Removal Rate (MRR) and decreases the Electrode Wear Rate (EWR). Surface finish is better when the lower order of capacitance and voltage is used. MRR is increased by 48% with best machining conditions compared to worst machining condition.

Purpose AA8090 aluminum alloy is used in industrial applications for weight reduction purposes. However, its usage is limited due to shortcomings such as low wear resistance. Hence, the purpose of this study is to improve the wear properties of the material. A particle strengthening mechanism was tried to improve the wear properties of materials. Design/methodology/approach AA8090 aluminum alloy composites were prepared by stir casting methods using AA8090, boron carbide (B4C) and aluminum oxide (Al2O3) materials. Totally, four different types of composites were prepared, namely, AA/3Al, AA/1BC-2Al, AA/2BC-1Al and AA/3BC. Wear behavior and mechanical properties of the composites were analyzed by conducting wear test, microhardness test, tensile test and morphological analysis. Findings Results showed that the composite materials showed superior properties compared with AA8090 alloy due to the reinforcing effect of B4C and Al2O3 particles. Further, the AA/3BC composite showed 12.9% and 10.8% enhancement in microhardness and tensile strength, respectively. Further, a minimum wear rate of 0.009 × 10–3 mm3/m was observed for AA/3BC composite. Originality/value This study is original and would add new information to the literature. Further, it solves the problem of low wear resistance issues in AA8090 aluminum alloy materials.

Electrode wear and metal removal exhibited nonlinear behavior in the Electrical Discharge Machining (EDM) of Hastelloy B2 plate. Hence, mathematical modeling was used to solve this problem. The hole size, pulse duration, duty cycle, and current were selected as inputs. Squareness and taper angle were considered as responses. Therefore, the Modified-Additive Ratio Assessment Method (M-ARAS) based Adaptive Neuro Fuzzy Inference System (ANFIS) method was used to find the optimum EDM process parameters. The overall analysis showed that the M-ARAS-based ANFIS algorithm provided a good fit for optimization of the process parameters and could be used for further multi-objective optimization problems.

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The silicon carbide (SiC) reinforcement with aluminium alloy 7xxx series has been found to be limited value as per the mechanical properties and wear behaviour of previous studies. In order to improve limited mechanical properties of hybrid aluminium metal matrix composites, the SiC and OFHC Cu-Fe29Ni17Co reinforcement has been added with AA7075 alloy. Hence, the AA7075/SiC/Cu-Fe-Ni hybrid composites have been fabricated through a stir casting route under different weight percentages of SiC reinforcement. The mechanical properties such as hardness, compressive strength, tensile strength and wear rate have been investigated. The micro structure of hybrid composites found that the reinforcement particles in matrix alloy have been evenly spread. The silicon carbide and Cu-Fe-Ni alloy in aluminium solid solution has been found as well bonded interfacial reactions. The hardness, tensile strength, yield strength, compressive strength and wear rate were improved by 23.9 %, 48 %, 47 %, 15.3 % and 70 % for hybrid composite by adding 15 wt. %SiC and 15 wt. % Cu-Fe-Ni with AA7075 alloy, compared to matrix alloy.