Effect of Combined Mechanical and Ultrasonic 16 07 2019· This study aims to investigate the effect of combined mechanical and ultrasonic milling on the size reduction of talc Firstly the talc sample was wet ground in a stirred media mill for five different times 30 60 90 120 and 150 min and the optimum result was subsequently achieved with treatment by ultrasonication The effects of amplitude 20 35 and 50 μm solid content 5 7