Fabrication of Molybdenum Nanopowder by Mechenochemical Process and its Sintering Characteristics

초록

Molybdenum (Mo), as one of the refractory metals, has been applied in high temperature industrial fields. Powder metallurgy (P/M) is a general process for the production of bulk Mo components because of its high melting point, 2610oC. Generally, sintering of commercial Mo powder with a particle size of several micrometers is performed at elevated temperatures for a long time. It has been reported that a Mo sintered body above 90% of theoretical density could be obtained over a sintering temperature range of 1800-2000oC for several hours. There have been some efforts to reduce the processing cost for a fully densified bulk component with an activated sintering that lowers the sintering temperature to 1200-1400oC through the addition of a small amount of Ni, Pt, Pd, and Co. These sintering aids, however, induce a deterioration of the electrical and thermal conductivity, as well as several mechanical properties