| The properties of Fe-Sn sintered compact for porous bearing and the phenomena appearing in heating process of Fe-1.0 Sn mixed powder compacts were investigated in comparsion with those of Fe powder compact, The results obtained are as follows. 1. When Fe-1.0 Sn mixed powder compact is sintered at temperatures above about 1000℃, the dimensional change and intercommunicating porosity are almost same with those of Fe compact, but the radial crushing strength is higher than that of Fe compact. 2. When Fe-1.0 Sn mixed powder compact is heated the liquid tin which formed at its melting point penetrates into capiliaries of Fe skeleton at temperatures above about 350℃. And with the rising temperature up to about 900℃, the Sn liquid react with Fe powder to form various Fe-Sn intermetallic compounds; θ, η, E and ζ. But at temperature above about 1000℃, all the intermetallic compounds became to a phase of Fe-Sn solid-solution having a higher self-diffusion coefficient than that of the γ phase. As a result Fe-1.0 Sn compact have a higher strength and more shrinkage ratio than Fe compact when sintered at temperatures above about 1000℃, which is usually employed in the case of sintering of Fe base compacts. |
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