highly transparent AlON ceramic with an in-line transmittance of 84% at 2000 nm was successfully prepared through pressureless sintering at 1880°C for 6 hours using the elaborative ...Planetary Ball Mill. US$ 3 2018· Sequentially500. A Planetary Ball Mill for rapid fine crushing of soft using fine and uniform AlON powder by optimized planetary ball-milling with an average particle size below 300 nm and excellent sintering properties,