OPTIMIZATION OF MACHINING PARAMETERS IN DRILLING OF HYBRID SISAL-BAMBOO FIBER REINFORCED EPOXY COMPOSITE FILLED WITH BAGASSE ASh

Abstract

Natural fiber reinforced composites (NFRCs) offers promising applications in the automotive industry, particularly for interior components. However, the inherent heterogeneous and abrasive nature of NFRCs presents significant challenges during the machining process, especially drilling, leading to defects such as roundness error and delamination of fibers. These drilling defects can hinder the practical use of NFRCs. To address these challenges, this study focuses on the optimization of machining parameters for drilling hybrid sisal bamboo fiber reinforced epoxy composites filled with bagasse ash. The mechanical properties characterization, including tensile, flexural, and impact strength tests, as well as water absorption tests, were conducted on three compositions to determine the most suitable hybrid composite for automobile interior applications. A series of drilling experiments were carried out using the L16 orthogonal array, varying spindle speed, feed rate, and drill diameter. The delamination factor and roundness error were measured using a digital camera, ImageJ software, and a digital caliper. The experimental results were analyzed using the Taguchi and Taguchi-GRA methods, and the optimum machining parameters were determined as a spindle speed, feed rate and drill diameter of 1750 rpm, 10 mm/min, and 6 mm respectively. Among the three composites investigated, Composite three(C3) exhibited the best properties, with tensile strength flexural strength, impact strength, and water absorption rate of 66.22MPa, 272.44MPa, of 4.777kJ/m, and 3.27% respectively. Verification tests confirmed the reliability of optimum parameters, with roundness error of 0.03 mm and delamination factor of 1.082. The findings of the study will contribute to improving the drilled hole quality in the drilling of NFRCs, which is crucial for the practical use of these particular NFRCs in the manufacturing of automobile interior parts.