Process for improving the adhesion of a lubricant to the surface of an aluminum strip

Abstract

A process for improving the adhesion of a lubricant to, and the distribution on, the surface of a strip of aluminum or aluminum alloy which is cold rolled between two work rolls, said cold rolled strip being coated with lubricant for the purpose of subsequent shape-forming, is such that the surface of at least one work roll exhibits a roughness pattern ( 10 ), which is comprised of at least two line patterns ( 14,18 ) that cross each other, whereby each of these line patterns is characterised by a plurality of parallel rills ( 12,16 ).

1 . A process for improving the adhesion to, and distribution of, a lubricant to the surface of a strip of one of an aluminum and aluminum alloy which is cold rolled between two work rolls, whereby the cold rolled strip is coated with lubricant for subsequent shape-forming, the process comprising providing on the surface of at least one work roll a roughness pattern ( 10 ), which is comprised of at least two line patterns ( 14 , 18 ) that cross each other, whereby each of these line patterns is characterised by a plurality of parallel rills ( 12 , 16 ) and rolling the strip with the surface of the at least one work roll.  
     
     
         2 . A process according to  claim 1 , wherein the roughness pattern ( 10 ) is comprised of two line patterns ( 14 , 18 ) that cross each other.  
     
     
         3 . A process according to  claim 2 , wherein the line patterns ( 14 , 18 ) make an angle (α,β) of 30° to 60° with the rolling direction (x).  
     
     
         4 . A process according to  claim 3 , characterised in that the line patterns ( 14 , 18 ) cross at an angle (α) of 90°.  
     
     
         5 . A process according to  claim 1 , wherein the distance (a) between the neighbouring rills ( 12 , 16 ) and the depth of the rills ( 12 , 16 ) lie between 0.2 and 2.5 μm.  
     
     
         6 . A process according to  claim 1 , wherein the distance (a) between the neighbouring rills ( 12 , 16 ) and the depth of the rills ( 12 , 16 ) lie between 0.4 and 1.8 μm.  
     
     
         7 . A process according to  claim 1 , wherein the roughness pattern ( 10 ) is created on the surface of both work rolls.