This study investigates the impact of process parameters on the quality and performance of bulk MgB 2 through ball milling. The research utilizes the Taguchi optimization process to optimize ball milling parameters, including RPM (revolution per minute), BPR (Ball Powder Ratio), and milling time. The effects of these parameters are evaluated using an orthogonal array. The L9 (3^3) Taguchi orthogonal array enables efficient problem-solving with fewer trials. Through this approach, the optimal combination of process parameters for high-energy ball milling is determined. The study achieves an optimal critical current density (Jc ) of 379.3 kA/cm^2 at 20 K through nine experiments. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses are employed to examine the shape and quality of the fine particles. The impact of process variables on the magnetic critical current density is analyzed using a main effects plot. After conducting an analysis of the experimental results using Minitab, the study successfully identifies the optimal combination of process parameters. The determined parameters consist of RPM set at level 2 (400 rpm), milling time set at level 2 (3 hours), and ball powder ratio set at level 1 (5:1). By applying these optimized parameters in subsequent runs on boron powders, a significant enhancement in critical current density is observed, resulting in an impressive value of 398 kA/cm^2 at 20 K, and this value further increases as the temperature decreases.
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Part of the funding for this work was provided by the Shibaura Institute of Technology (SIT) International Research Centre for Green Electronics and Grant-in-Aid FD research budget. Furthermore, we would like to acknowledge that Malik Shadab, one of the authors, received generous financial assistance from SIT throughout their doctoral program.