EP 0839920 A3 20000329 - Process for preparing a starting powder material for fine grained hard metal
Title (en)
Process for preparing a starting powder material for fine grained hard metal
Title (de)
Verfahren zur Herstellung von Pulvervormaterial für feinkörniges Hartmetall
Title (fr)
Procédé de préparation de poudre de départ pour matériau dur à grain fin
Publication
Application
Priority
AT 191296 A 19961104
Abstract (en)
[origin: EP0839920A2] In the production of a starting powder for fine grained cemented carbide manufacture from a metal oxide or reducible metal compound powder by reducing to metal, carburizing and subjecting to a mechanical-chemical powder treatment and/or mixing operation, the reduction and/or carburization step employs a cyclone unit which is a heated rotationally symmetrical reaction chamber having inlet and outlet openings for the powder, reagent and carrier gas. The continuously supplied powder retains its solid state during high velocity passage through the reaction chamber along predetermined flight paths which are tangential to the chamber wall and which are controlled by means of the powder flight direction and velocity at the inlet and by means of the flow parameters of the carrier and/or reaction gas. The unit produces ≥ 90 vol.% chemical reaction of the powder in a dwell time of 0.1-60 (preferably 0.2-10) s.
IPC 1-7
IPC 8 full level
B22F 9/22 (2006.01); B22F 1/00 (2006.01); C22C 1/05 (2006.01)
CPC (source: EP US)
C22C 1/056 (2013.01 - EP US); B22F 2998/00 (2013.01 - EP US)
C-Set (source: EP US)
Citation (search report)
- [PX] WO 9716275 A1 19970509 - PLANSEE AG [AT], et al
- [A] US 5125964 A 19920630 - BUERKEL WILLIAM A [US], et al
- [A] FR 941412 A 19490111 - PLURO INC
- [A] FR 844368 A 19390724
Designated contracting state (EPC)
AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
EP 0839920 A2 19980506; EP 0839920 A3 20000329; EP 0839920 B1 20021218; AT 404912 B 19990325; AT A191296 A 19980815; AT E230038 T1 20030115; DE 59709001 D1 20030130; ES 2186840 T3 20030516; JP H10140216 A 19980526; US 6113668 A 20000905
DOCDB simple family (application)
EP 97203354 A 19971029; AT 191296 A 19961104; AT 97203354 T 19971029; DE 59709001 T 19971029; ES 97203354 T 19971029; JP 31283597 A 19971029; US 96210297 A 19971031