Production of low impurity aluminium rotor for motor efficiency enhancementSavitri Payakkapol, Nattapon Chayopitak, Panya Kunsuwan, Naoto Ohtake and Sompong SrimanosaowapakMATEC Web Conf., 192 (2018) 01043DOI: https://doi.org/10.1051/matecconf/201819201043