| 摘要 |
The mandrel (1) for cold and/or hot forming of metal is provided, in the region of working and high-temp. bands (L3,L4), with protective anti-wear and anti-friction layers (L1',L1'') of great high-temp. strength. These layers alternate with one or more annular uncoated, springy depressions (L5) reducing the mandrel dia. The layers (L1',L1'') are produced by powder application welding by means of laser radiation, with a subsequent finish treatment. The mandrel is used as a piercing mandrel, for piercing and stretching of round steel bars and/or hollow blanks in helical hot-rolling mills. USE/ADVANTAGE - In metal forming technology, in partic. in tube-rolling mills. Mandrels produced according to this method have a longer life than those produced by other methods, while the mfr. such mandrels is simpler than by certain other methods. |
| 申请人 |
FRAUNHOFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWANDTEN FORSCHUNG EV, 80636 MUENCHEN, DE |
发明人 |
PAUL, HEINRICH, DR., O-8101 PAPPRITZ, DE;POLLACK, DIETER, DR., O-8021 DRESDEN, DE;LEUTERITZ, HAGEN, O-8403 NUENCHRITZ, DE;PIETSCH, JUERGEN, DR., 4050 MOENCHENGLADBACH, DE;KRIESE, JENS, 5900 SIEGEN, DE |
