| 摘要 |
1. A heat treatable Al-Mg-Si aluminum alloy which after shaping has been submitted to an ageing process, characterized in that the ageing after cooling of the extruded product is performed in two stages, at a first stage in which the extrusion is heated with a heating rate above 100 degree C/hour to a temperature between 100-170 degree C, a second stage in which the extrusion is heated with a heating rate between 5 and 50 degree C/hour to the final hold temperature between 160 and 220 degree C and in that the total ageing cycle is performed in a time between 3 and 24 hours. 2. Aluminium alloy according to Claim 1, any one of the preceeding Claims, characterized in that after the first ageing step a hold of 1 to 3 hours is applied at a temperature between 130and160 degree C. 3. Aluminium alloy according to any one of the preceeding Claims, characterized in that the final ageing temperature is at least 165 degree C. 4. Aluminium alloy according to any one of the preceeding Claims, characterized in that the final ageing temperature is at most 205 degree C. 5. Aluminium alloy according to any one of the preceeding Claims, characterized in that in the second heating stage the heating rate is at least 7 degree C/hour. 6. Aluminium alloy according to any one of the preceeding Claims, characterized in that in the second heating stage the heating rate is at most 30 degree C/hour. 7. Aluminium alloy according to any one of the preceeding Claims, characterized in that at the end of the first heating step the temperature is between 130 and 160 degree C. 8. Aluminium alloy according to any one of the preceeding Claims, characterized in that the total ageing time is at least 5 hours. 9. Aluminium alloy according to any one of the preceeding Claims, characterized in that the total ageing time is at most 12 hours. |
