NEW TECHNOLOGY FOR COMPOSITES BASED ON TUNGSTEN POWDER OBTAINING

摘要

This paper presents a study on the quality of composites, based on tungsten powder, realized by a new proposed technology, which eliminates the operation of the paraffin infiltration and, also, the uniaxial die compaction that is the dominant mode of powder compaction. But the powder does not respond uniformly to the applied pressure, consequently obtaining the target density and the strength levels are the primary concerns. Because tungsten is a powdery metal with a high melting temperature, the technical itinerary of sintering with liquid phase, typical for Powder Metallurgy, is the only mechanism that produces heavy alloys with a high density. Also, for eliminate the operation of the paraffin infiltration, it was tested with copper 2% as an additional element and then prepared through isostatic pressing. N this studyt is underlined the influence of some technological parameters on the quality of these pseudoalloys. Finally, a comparative study has been made between the final values of the hardness, density and the microstructural aspects, of these composites based on W-powder, obtained through the new proposed technology and the actual technology by Powder Metallurgy.