PROCEDIMENTO E DISPOSITIVO PER LOSTAMPAGGIO DI ARTICOLI MEDIANTE COMPATTAZIONE DI POLVERI PARTICOLARMENTE DI MATERIALE METALLICO O CERAMICO

Vol. of powder material is constrained within a mould against an element having a thermal expansion characteristic differing from that of the mould. The temp. of the element is changed over a range which, a a result of the vol. thermal expansion differences, causes compression of the powder into a formed article. Used in compaction of metallic powders, ceramic powders. Use of the vol. expansion effect members in formation of a high density article approaching 100% density at lower temps. than are required for sintering the powders. The low temps. avoid grain growth characteristics of compaction by sintering. The mould may be used repeatedly to avoid the high cost of refixturing. The compression force can be controlled by proper design of the mould and location of the high expansion material surrounding the powder compact.