抄録
In order to investigate the expansion of Fe-Cr3C2 compacts during sintering, the dilatometric analysis and microscopic examination were systematically carried out by using Fe-Cr3C2 mixed powder compacts which contain up to 30 wt % Cr3C2.
The results were summarized as follows:
(1) An abnormal expansion appeared in the temperature range between 1050° and 1250°C, and the expansion increased with the increase of Cr3C2 content in the compacts up to 10 wt % Cr3C2, but at higher contents decreased with the increase of Cr3C2 content.
(2) This expansion appeared not only in the compacts prepared with reduced iron powders, but also in those of electrolytic, pulverizied electrolytic and carbonyl iron powders, although some difference were observed between them.
(3) The expansion observed in the Fe-Cr3C2 compacts did not appear in Fe-Cr, Cr-C, Fe-C and Fe-Cr-C mixed powder compacts, but in the 8.7 Cr-1.3C-Fe mixed powder compacts which corresponding to 10 wt % Cr3C2-Fe there appeared at high temperature.
(4) Changes in dimensions of specimens under elevated temperature could be well accounted for from their change in the microstructures.
