Abstract
In order that the problems encountered with a low density of MIM brown parts solve, such as lower sintered density due to a poor sinterability or shape . distortion due to the excessive shrinkage, the repressing treatment of the debound part was newly introduced as a post debinding treatment for MIM of various powders.
The various MIM green parts molded with a mixed binder system were debound by thermal debinding process. The debound parts sealed with a thin rubber mold were then isostatically pressed at the maximum pressure of the 550MPa.
The sintered density of Fe-MIM parts was improved remarkably by an additional pressing treatment of the MIM debound parts, especially for the MIM part made of the coarse Fe powders. Such an isostatic pressing treatment exerted a good effect on the shape stability of the MIM parts during sintering and also on their sintered properties.
