| 摘要 |
The method comprises prodn. of components out of powder materials, in partic., metal powders, by successive superpositioning of material layers, followed each time by selective thermal bonding of the layers to one another (according to the shape of the cross section at a given level), and removal of the non-bonded material.Before positioning of each layer, its material is compacted by application of a pressure of at least 350 N/mm2 into a flat, plate-like body. Selective thermal bonding of the layers takes place by means of a welding process, and the vol. contraction caused by this process is largely compensated by addition of further material during or after bonding.Compaction of material layers takes place separately in a powder press. Alternatively, it takes place in a rolling installation. Again, compaction takes place in two stages, first in a powder press and then in a rolling installation. A pressure of at least 800 N/mm2 is used, with a vol. red. of at least 70 per cent. The thickness of the compacted layers whose material can vary from zone to zone lies within the range 0.1-2 mm.
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