nusyirwan, nusyirwan, & Fikri, H. (2026). Study on the Flexural Strength of Polyester Composite Beams and Coconut Husk Charcoal Powder. Jurnal Teknik Mesin (Journal Of Mechanical Engineering), 15(01), 83–89. https://doi.org/10.22441/jtm.v15i01.23591