Sintered self-lubricating bearings are a classic example of how the porosity of sintered components, normally considered one of their greatest weaknesses, can become a key functional requirement. Typically these products are based on sintered CuSn10 bronze alloys with graphite additions, but for less demanding applications iron-copper combinations are also well established materials. Given the low compaction densities required to achieve a significant amount of final porosity, and the relatively low sintering temperatures, a careful design of iron and copper powders is necessary to achieve desirable dimensional and mechanical properties in both green and sintered state. In this experimental work, different PM solutions are studied, both existing and newly developed, for a constant metallic composition of iron plus 20 weight percent copper. A characterization of flow, compaction, dimensional, mechanical and microstructural behaviour is given, for different sintering conditions. Advantages and disadvantages of the new products are finally evaluated.
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