Extrusion of a Metal Alloy Containing Copper and Zinc

Abstract

The invention relates to a method for producing a metal alloy product ( 19 ) containing at least some amount of β-phase brass by extrusion, a metal alloy product produced by extrusion of metal alloy containing at least some amount of β-phase brass, an extrusion die ( 15 ) for extrusion of a metal alloy containing copper and zinc, and at least some amount of β-phase, an extrusion device, and a use of a metal alloy for extrusion.

1 . A method for producing a metal alloy product comprising:
 feeding ( 29 ) a metal alloy containing copper and zinc, and at least some amount of β-phase brass to an extrusion die, and   extruding ( 31 ) the metal alloy containing the β-phase through at least one extrusion opening in said extrusion die ( 15 ), the opening ( 17 ) being shaped so that the distance between at least two opposite sides of the opening is smaller than or equal to 1 mm.   
     
     
         2 . A method according to  claim 1 , wherein the distance is smaller than or equal to 0.3 cm, preferably smaller than or equal to 1 mm, and most preferably smaller than or equal to 0.7 mm. 
     
     
         3 . A method according to  claim 1 , wherein the metal alloy is extruded at a temperature higher than 450° C., preferably higher than 550° C., and more preferably higher than 600° C. 
     
     
         4 . A method according to  claim 1 , wherein the metal alloy is extruded at a temperature lower than 900° C., preferably lower than 800° C., and more preferably lower than 700° C. 
     
     
         5 . A method according to  claim 1 , wherein the method comprises:
 pre-heating ( 27 ) the metal alloy before extrusion to a temperature between 500° C. and 700° C.   
     
     
         6 . A method according to  claim 1 , wherein the metal alloy comprises more than or equal to 35 weight % of Zinc, preferably more than or
 equal to 38 weight % of Zinc, and most preferably more than or equal to 42 weight % of Zinc, the balance being copper and inevitable impurities.   
     
     
         7 . A method according to  claim 1 , wherein the metal alloy comprises less than or equal to 55 weight % of Zinc, preferably less than or equal to 50 weight % of Zinc, and most preferably less than or equal to 48 weight % of Zinc. 
     
     
         8 . A method according to  claim 1 , wherein the method comprises extruding the metal alloy in a continuously operated extrusion device ( 1 ). 
     
     
         9 . A method according to  claim 1 , wherein the method comprises producing an elongated multiform product ( 19 ). 
     
     
         10 . A method according to  claim 1 , wherein the method comprises producing a multi-port or multichannel profile ( 19 ). 
     
     
         11 . A method according to  claim 10 , wherein the method comprises producing a multi-channel profile ( 19 ) or tube ( 24 ) adapted for use in a heat transport device, such as a heat exchanger or heat pump. 
     
     
         12 . A method according to  claim 1 , wherein the method comprises producing a multi-channel profile ( 19 ) or tube ( 24 ) adapted for use in a vehicle heat-exchanger by extrusion of a metal alloy containing copper and zinc, and at least some amount of β-phase brass. 
     
     
         13 . An extruded metal alloy product containing copper and zinc, and at least some amount of β-phase, wherein the product ( 19 ) comprises at least one wall section ( 23 ) with a thickness smaller than or equal to 1 mm. 
     
     
         14 . An extruded metal alloy product according to  claim 13 , wherein the product is a profile ( 19 ) for a multichannel tube ( 24 ) adapted for use in a heat transporting device. 
     
     
         15 . An extrusion die adapted for extrusion of a metal alloy containing copper and zinc, and at least some amount of β-phase, wherein the die ( 15 ) is shaped with an extrusion opening ( 17 ) shaped so that the distance between at least two opposite sides ( 21   a ,  21   b ) of the opening is smaller than or equal to 1 mm. 
     
     
         16 . An extrusion die according to  claim 15 , wherein the extrusion die ( 15 ) is adapted to be used in a continuously operated metal alloy extrusion device ( 1 ). 
     
     
         17 . An extrusion device adapted for extrusion of a metal alloy comprising copper and zinc, and at least some amount of β-phase, wherein the extrusion device ( 1 ) comprises an extrusion die ( 15 ) provided with an extrusion opening ( 17 ) shaped so that the distance between at least two opposite sides ( 21   a ,  21   b ) of the opening is smaller than or equal to 1 mm. 
     
     
         18 . A use of a metal alloy containing copper and zinc, and at least some amount of β-phase in the extrusion of a metal alloy product having a wall section ( 23 ) with a thickness smaller than or equal to cm 1 mm.