Method for the manufacturing of products with anodized high gloss surfaces from extruded profiles of al-mg-si or al-mg-si cu extrusion alloys

Abstract

Method for the manufacturing of products with anodized high gloss surfaces from extruded profiles of Al—Mg—Si or AS-Mg—Si—Cu, where the alloys initially are cast to extrusion billets), containing in wt. % Si: 0.25-1.00 Mg. 0.25-1.00 Fe: 0.00-0.15 Cu: 0.00-0.30 Mn: 0.00-0.20 Cr: 0.00-0.10 Zr: 0.00-0.10 Se: 0.00 -0.10 Zn: 0.00-0.10 Ti: 0.00-0.05., and including incidental impurities and balance A.L a) where the billet is homogenised at a holding temperature between 480° C. and 620° C. and soaked at this temperature for 0-12 hours, where after the billet is subjected to cooling from the homogenisation temperature at a rate of 150° C./h or faster, b) the billet is preheated to a temperature between 400 and 540° C. and extruded preferably to a solid shape profile and cooled rapidly down to room temperature, c) optionally artificially ageing the profile, d) deforming the profile more than 10% by a cold roiling operation, whereafter e) the profile is flash annealed with a healing time of maximum two minutes to a temperature of between 450-530° C. for not more than 5 minutes and subsequently quenched, and f) optionally the profile after flash annealing is further subjected to a cold deforming operation to remove residual stresses from cooling and adjusting dimensional tolerances, and g) the profile is finally aged.

1 - 12 . (canceled) 
     
     
         13 . Method for the manufacturing of products with anodized high gloss surfaces from extruded profiles of Al—Mg—Si or Al—Mg—Si—Cu alloys, where the alloys initially are cast to extrusion billet(s), containing in wt. %
 Si: 0.25-1.00 
 Mg: 0.25-1.00 
 Fe: 0.00-0.15 
 Cu: 0.00-0.30 
 Mn: 0.00-0.20 
 Cr: 0.00-0.10 
 Zr: 0.00-0.10 
 Sc: 0.00-0.10 
 Zn: 0.00-0.10 
 Ti: 0.00-0.05, and 
 including incidental impurities and balance Al,
 a) where the billet is homogenised at a holding temperature between 480° C. and 620° C. and soaked at this temperature for 0-12 hours, whereafter the billet subjected to cooling from the homogenization temperature at a rate of 150° C./h or faster, 
 b) the billet is preheated to a temperature between 400 and 540° C. and extruded preferably to a solid shape profile and cooled rapidly down to room temperature, 
 c) optionally artificially ageing the profile, 
 d) deforming the profile more than 10% by cold rolling operation, whereafter 
 e) the profile is flash annealed with a heating time of maximum two minutes to a temperature of between 450-530° C. for not more than 5 minutes and subsequently quenched, and 
 f) optionally the profile after flash annealing is further subjected to a cold deforming operation to remove residual stresses from cooling and adjusting dimensional tolerances, and 
 g) the profile is finally aged. 
 
 
     
     
         14 . Method according to  claim 13 ,
 wherein the composition of the alloys measured in wt. % lies preferably within
 Si: 0.35-0.6 
 Mg: 0.35-0.6 
   and the following maximum levels (wt. %) of the following elements
 Fe: 0.09 
 Cu: 0.15 
 Mn: 0.06 
 Cr: 0.04 
 Zn: 0.03 
 Ti: 0.02, and 
   including incidental impurities and balance Al.   
     
     
         15 . Method according to  claim 13 ,
 wherein the composition of the alloys measured in wt. % lies preferably within
 Si: 0.35-0.6 
 Mg: 0.35-0.6 
   and with the following maximum levels (wt. %) of the following elements
 Fe: 0.06 
 Cu: 0.12 
 Mn: 0.06 
 Cr: 0.04 
 Zn: 0.03 
 Ti: 0.02, and 
 including incidental impurities and balance Al. 
   
     
     
         16 . Method according to  claim 13 ,
 wherein the profile in accordance with step c) optionally is overaged to a T7 condition at 200-230° C. for 1-5 hours.   
     
     
         17 . Method according to  claim 13 ,
 wherein the profile according to step d) is deformed more than 20%.   
     
     
         18 . Method according to  claim 13 ,
 wherein the profile according to step d) preferably is deformed between 30 and 50%.   
     
     
         19 . Method according to  claim 13 ,
 wherein the profile is flash annealed according to step e) with a maximum heating time of 20 seconds to a temperature of between 450-530° C. for more than 1 minute.   
     
     
         20 . Method according to  claim 13 ,
 wherein the flash anneal heating according to step e) is obtained by induction heating of the profile.   
     
     
         21 . Method according to  claim 13 ,
 wherein the flash anneal heating according to step e) is obtained by subjecting the profile to a salt bath or other convection or radiation heating means providing high heating rates.   
     
     
         22 . Method according to  claim 13 ,
 wherein the alloys are cast without the use of grain refiner, except in the start-up of the casting operation.   
     
     
         23 . Method according to  claim 13 ,
 wherein the ageing, step g) is a one step or dual rate ageing operation to a final hold temperature between 160° C. and 220° C. and where the total ageing cycle is performed in a time span of between 3 and 24 hours.   
     
     
         24 . Method according to  claim 13 ,
 wherein the optical cold deforming after flash annealing, step f) is a rolling operation, a stretching operation or a forging operation.