Abstract
A study was carried out to investigate the possibility whether MIM process could be applied to the compacting process of W-Ni-Fe heavy alloy in order to obtain an intricate shape. The multi binder system of 45PW+30PE+15BW+10SA was used for injection molding and compacts from the powder-binder mixture of metal powder fraction of 60 vol.% were studied for debinding and sintering behaviors. In debinding process, heating rate in temperature range from 120°C to 290°C had an important effect on the weight loss of the binder. The binder could be fully removed by three stage debinding treatment. The microstructure of the sintered specimen was dependent on the sintering atmosphere. The W-4.9wt.%Ni-2.1wt.%Fe alloy of full sintered density was obtained by sintering at 1470°C for 1 h in a wet hydrogen atmosphere and there was no difference in microstructure compared to that of W heavy alloy by die compaction.
