(19)

(11)

EP 0 222 002 A1

(12)

(43) Date of publication: 20.05.1987 Bulletin 1987/21 (21) Application number: 86903818.0 (22) Date of filing: 15.05.1986

(51) International Patent Classification (IPC):  B22F 1/ 00( . ) C21D 1/ 00( . ) B22F 3/ 24( . ) C22C 1/ 04( . ) (86) International application number: PCT/US1986/001050 (87) International publication number: WO 1986/006748 (20.11.1986 Gazette 1986/25)

(84) Designated Contracting States: FR GB (30) Priority: 17.05.1985 US 19850735567 07.05.1986 US 19860860546 (71) Applicant: ALUMINUM COMPANY OF AMERICA Pittsburgh, PA 15219 (US)	(72) Inventors: RIOJA, Roberto, J. Lower Burrell, PA 15068 (US) DENZER, Diana, K. Lower Burrell, PA 15068 (US) (74) Representative: Baillie, Iain Cameron, et al  c/o Ladas & Parry Altheimer Eck 2 D-80331 München D-80331 München (DE)