Abstract

This paper describes the manufacturing process of tilting pad gas bearing with a diameter of 5 mm and a length of 0.5-1 mm for power MEMS (Micro Electomechanical Systems) applications. The bearing compacts with nanopowder feedstock were prepared by Ni-metal mold with 2-mold system using LIGA process. The effect of the manufacturing conditions on sintering properties of nanopowder gas bearing was investigated. In this work, Fe-45 wt%Ni nanopowder with an average diameter of 30-50 nm size was used as starting material. After mixing the nanopowder and the wax-based binders, the amount of powder was controlled to obtain the certain mixing ratio. The nanopowder bearing compacts were sintered with 1-2 hr holding time under hydrogen atmospheres and under temperatures of 600°C to 1,000°C. Finally, the critical batch of mixed powder system was found to be 70% particle fraction in total volume. The maximum density of the sintered bearing specimen was about 94% of theoretical density.

• Keywords: Micro bearing;Fe-Ni nanopowder;Wax-based binder system;LIGA process;