Predictive modelling and optimization of WEDM parameter for Mg-Li alloy using ANN integrated CRITIC-WASPAS approach.

This work intended to improve the precision and machining efficiency of Magnesium alloy (Mg-Li-Sr) using Wire electrical discharge machining (WEDM). Mg-Li-Sr alloy is prepared through inert gas assisted stir casting route. Taguchi approach is used for experimental design for WEDM parameter such as pulse OFF time, pulse ON time, wire feed rate, servo voltage and current. L27 orthogonal array is considered to understand the influence of control parameter such as Kerf Width (KW), Roughness of the surface (Ra), Material Removal Rate (MRR). Integration of the CRITIC (Criteria Importance Through Intercriteria Correlation) -WASPAS (Weighted Aggregated Sum Product Assessment) multi-objective optimization method with Artificial Neural Network (ANN) modelling with different network structure for prediction and optimization is a novel approach that significantly improves prediction accuracy and machining outcomes. The developed ANN model with better R2 value of 99.9 % has better ability for prediction while correlated with formulated conventional regression equation. The error percentages identified through confirmation tests for regression and ANN models are Ra - 8.5 % and 3.4 %, MRR - 5.9 % and 2.8 %, KW - 6.7 % and 2.2 % respectively. Optimal output response attained by CRITIC-WASPAS approach yields surface roughness of 4.62 µm, material removal rate of 0.073 g/min and kerf width of 0.388 µm.

Extraction and characterization of novel Prosopis Juliflora bark and Boehmeria nivea fibre for use as reinforcement in the hybrid composites with the effect of curing temperature, fibre length and weight percentages.

The hybrid composite sample based on Prosopis Juliflora (PJ) bark and ramie fibre with different length, weight percentage, and curing temperature were created for the first time in this work. Totally, 120 hybrid composite samples were tested in this study. There were five different fibre lengths: 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm, weight percentages 10 %, 20 %, 30 %, 40 %, and 50 %, and different curing temperatures 80 °C, 90 °C, 100 °C, 110 °C, and 120 °C used to produce the hybrid composite samples. Due to the cross-linking ability with the epoxy matrix, the hybrid composite specimen shows high resistance up to 98 Shore D hardness. The high polarity of the epoxy matrix and the hydrogen bond strengthening effect, increased the composite sample flexural strength by 12 %. The curing temperature of 100 °C, 20 mm fibre length, and 30 % of the hybrid composite sample achieved the highest tensile strength (28.76 MPa), flexural strength (46.54 MPa), impact strength (4.5 J), and hardness strength properties (98 shore D). Thermo gravimetric analysis (TGA) revealed the composite samples initial decomposition temperature (Ti) at 98 °C, maximum decomposition temperature (Tmax) at 320 °C, and the final decomposition temperature (Tf) at 466 °C.