| 主权项 |
1. Method for the manufacturing of an Al—Mg—Si(—Cu) extrusion alloy, the alloy initially being cast to extrusion billet(s), containing in wt. %Si: 0.20-1.50Mg: 0.25-1.50Fe: 0.05-0.50Cu: 0.00-1.00Mn: 0.00-1.00Cr: 0.00-0.50Zn: 0.00-0.50Ti: 0.00-0.20, and
including incidental impurities and balance Al, where the billet, depending on its alloy composition and application, is heated to the desired homogenisation holding temperature T1 between 520° C. and 620° C. and held at said temperature for a required time, where after the billet is subjected to cooling from the homogenisation temperature T1 to a temperature T2, or cooling to a temperature T3 lower than T2 and then reheating to T2, before onset of cooling at a rate of 150° C./h or faster, and where the homogenisation temperature T2 is at least 10° C. lower than the temperature T1, and where the time between the temperature T1 and the onset of cooling at a rate of 150° C./h or faster starting at the temperature T2 is minimum 30 minutes and maximum 20 hours. |
