Sintering behavior of molybdenum nanopowder prepared by mechanochemical process

Abstract

Mo nanopowder was successfully synthesized by mechanochemical process of MoO3 powder. The crystalline size of the MoO3 powder was decreased to below 10 nm by a 20 h ball-milling process. After hydrogen reduction at 800oC, 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 10oC/min to a higher temperature T1 (1000-1200oC), then immediately cooled to a lower temperature T2 (900-1000oC) and then isothermal sintering was accomplished at the T2 for 3-20 h. After sintering, sintered density and grain size was compared with samples by conventional sintering.