| 摘要 |
PCT No. PCT/FI95/00514 Sec. 371 Date Mar. 21, 1997 Sec. 102(e) Date Mar. 21, 1997 PCT Filed Sep. 20, 1995 PCT Pub. No. WO96/09132 PCT Pub. Date Mar. 28, 1996The invention relates to a method for the fabrication of dimensionally accurate metal pieces by sintering a material which, before the sintering, consists of a blend of three pulverous ingredients, of which the first ingredient is in the main an iron-group metal, the second ingredient is in the main copper and phosphorus, and the third ingredient is an alloy of copper and some other metal. The shape of the piece is produced by layer-by-layer freeform selected area laser sintering, wherein a layer of the said powder blend is spread on a base, those regions of the layer which correspond to this cross-sectional surface of the piece are heated by a laser beam to the sintering temperature. Thereafter further successive powder layers are spread one on top of another, and in each layer in turn those areas which correspond to the cross-sectional surface of the piece in that layer are laser sintered. The sintering takes place in a gas atmosphere which contains a chemical compound of some iron-group metal, the compound decomposing at the sintering temperature, in which case the iron-group metal will deposit into those cross-sectional areas of the piece being sintered at a given time. |
