Aluminium composite material and forming method
The invention relates to a method for forming an aluminum composite material which has a core alloy made from an aluminum alloy of type AA5xxx or AA6xxx and at least one outer aluminum alloy layer provided on one or both sides, wherein the aluminum composite material is formed and the outer aluminum alloy layer provided on one or both sides has a yield strength R p0.2 of 25 MPa to 60 MPa in the soft or solution-annealed state. The method enables the production of large-surface, heavily formed aluminum alloy sheet metal parts, in particular also in outer skin quality.
1. A method for forming a component from an aluminium composite material, the method comprising the steps of:
providing a core alloy made from an aluminium alloy and at least one outer aluminium alloy layer provided on one or both sides;
forming the aluminium composite material in a forming tool to form the component; and
wherein the at least one outer aluminium alloy layer provided on one or both sides has a yield strength R p0.2 of 25 MPa to 60 MPa and a shear flow stress k outside in a soft or solution-annealed state,
wherein, k f,outside /k f,core <0.5 applies for flow stresses of the aluminium alloys of the core and of the at least one outer layer in the soft or solution-annealed state,
wherein frictional shear stress τ R between the forming tool and the aluminium composite material in a contact surface reaches the shear flow stress k outside of the at least one outer aluminium alloy layer at at least one local position in the forming tool during the forming of the component;
wherein, the forming comprises a deep drawing and/or stretch forming procedure; and
wherein the core alloy is an alloy of type AA6xxx and the at least one outer aluminium alloy layer is an aluminium alloy of type AA8xxx or the core alloy is AA5xxx and the at least one outer aluminium alloy layer is an aluminium alloy of type AA8079, AA1050, AA5005, AA5005A.
2. The method according to claim 1 , wherein at least one outer aluminium alloy layer having a thickness of 5% to 15% of the total aluminium composite material is formed.
3. The method according to claim 1 , wherein the step of forming includes the step of enlarging the frictional shear stress τ R by increasing a surface pressure between the aluminium composite material and a hold-down clamp of the forming tool.
4. The method according to claim 1 , wherein the step of providing the core alloy includes the step of providing the core alloy as the core alloy of type AA6xxx having a uniform strain A g of at least 20% in the solution-annealed or soft state.
5. The method according to claim 4 , wherein the step of providing the aluminium core alloy and at least one outer aluminium alloy layer includes the step of providing the aluminium core alloy as an aluminium core alloy of type AA6016 and the at least one outer aluminium alloy layer as type AA8079.
6. The method according to claim 1 , wherein the formed component having the AA6xxx aluminium core alloy has a thickness of 0.5 mm to 2.0 mm.
7. The method according to claim 1 , wherein the formed component having the AA5xxx aluminium core alloy is AlMg6 and has a thickness of 1.0 mm to 2.0 mm.
8. The method according to claim 1 , wherein the formed component having the AA6xxx aluminium core alloy has a thickness of 0.7 mm to 1.8 mm.
9. The method according to claim 1 , wherein the formed component having an aluminium composite material has an AA6xxx aluminium core alloy has a thickness of 0.7 mm to 1.8 mm.
10. The method according to claim 1 , wherein the formed component having the aluminium composite material has an AlMg6 aluminium core alloy having a thickness of 0.5 mm to 3.5 mm.
11. The method according to claim 1 , wherein the formed component having the AA6xxx aluminium core alloy has a thickness of 0.8 mm to 1.5 mm.
12. The method according to claim 1 , wherein the step of providing the core alloy includes the step of providing the aluminium core alloy as the aluminium core alloy of type AA6xxx having a uniform strain A g of at least 22% in the solution-annealed or soft state.
13. The method according to claim 1 , wherein the step of providing the core alloy includes the step of providing the aluminium core alloy as AlMg6 having a uniform strain A g of at least 20% in the solution-annealed or soft state.
14. The method according to claim 1 , wherein the step of providing the core alloy includes the step of providing the aluminium core alloy as AlMg6 having a uniform strain A g of at least 22% in the solution-annealed or soft state.