Sintering Behavior of Molybdenum Nanopowder Prepared by Mechanochemical Process

摘要

Mo nanopowder was successfully synthesized by mechanochemical process of MoO_3 powder. The crystalline size of the MoO_3 powder was decreased to below 10 nm by a 20 h ball-milling process. After hydrogen reduction at 800 deg C, the crystalline size of the Mo powder was about 60 nm. Mo nanopowder was sintered using various two-step sintering schedules. The green parts were heated at 10 deg C/min to a higher temperature Ti (1000-1200 deg C), then immediately cooled to a lower temperature T_2 (900-1000 deg C) and then isothermal sintering was accomplished at the T_2 for 3-20 h. After, sintering, sintered density and grain size was compared with samples by conventional sintering.