Ball Milling Method for Nanomaterial Fabrication and Structures Modification 8-16 Oktaviana Dyah Mayasari*, Fitri Siti Sholikhah, Khofifah Cyntia Laras, Nikmatuz Zuhrini Azizah, Nurul Fatimah, Salma Akramia, Vanani Nur Rizki, Teguh Endah Saraswati Chemical