PRODUCTION OF ALUMINUM PLATE TO BE USED FOR VACUUM

• Main Authors: ISOYAMA EIZOU, TSUKAMOTO KENJI
• Format: Patent
• Language: English
• Published: 01.09.1984
• Subjects: AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS ANDNON-FERROUS ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; PERFORMING OPERATIONS; PUNCHING METAL; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PURPOSE:To produce an Al plate to be used for vacuum by extrusion-forming a hollow extrusion shape of Al having at least one partition wall in the inside by preventing the inside of the shape from contacting with atmospheric air, and separating the partition wall from the peripheral wall by cutting. CONSTITUTION:In the production of Al plate required to have characteristics for maintaining vacuum for such as electrode plates of ion pump, etc., Al billet 2 is extruded from a die 5 to produce a formed material 15 having >= one partition wall 16 by extrusion-forming. In this extrusion stage, a gaseous mixture consisting of 7% O2 and 93% Ar is supplied from a bomb 12 to the space 17 between the partition walls 16 in the formed material 15, and the top end 18 of the material 15 is sealed 19 tightly. The material 15 contg. the sealed gas is cooled and straightened by tensioning, and heat-treated further at 180 deg.C for 6hr. Thereafter, the sealing parts at both ends 18, 19 are cut off, thus, an Al plate having a thin and dense oxide film on the surface is obtd. from the partition wall which is useful as a preferred material for an electrode of an ion pump.