Automobile body part
View Patent ↗The present invention relates to an automotive clad sheet product comprising a core layer and at least one clad layer wherein the core comprises an alloy of the following composition in weight %: Mg 0.45-0.8, Si 0.45-0.7, Cu 0.05-0.25, Mn 0.05-0.2, Fe up to 0.35, other elements (or impurities) <0.05 each and <0.15 in total, balance aluminum; and the at least one clad layer comprises an alloy of the following composition in weight %: Mg 0.3-0.7, Si 0.3-0.7, Mn up to 0.15, Fe up to 0.35, other elements (impurities) <0.05 each and <0.15 in total, balance aluminum. The clad automotive sheet product provides excellent hemmability which does not substantially change over time and yet also provides a good age-hardening response after bake hardening.
1. An automotive clad sheet product comprising a core layer and at least one clad layer wherein the core layer comprises an alloy of the following composition in weight %:
Mg
0.45-0.8
Si
0.45-0.7
Cu
0.05-0.25
Mn
0.05-0.2
Fe
up to 0.35
with other elements <0.05 each and <0.15 in total, and the balance aluminium; and the at least one clad layer comprises an alloy of the following composition in weight %:
Mg
0.3-0.7
Si
0.3-0.7
Mn
up to 0.15
Fe
up to 0.35
with other elements <0.05 each and <0.15 in total, and the balance aluminium,
wherein the bending factor, as measured according to ASTM E290, is below 0.3 after 6 months natural ageing.
2. The clad sheet product according to claim 1 , wherein the product comprises two clad layers with one clad layer on each side of the core layer.
3. The clad sheet product according to claim 2 , wherein the two clad layers are of the same composition.
4. The clad sheet product according to claim 1 , wherein the Mg content in the at least one clad layer is 0.4-0.6.
5. The clad sheet product according to claim 1 , wherein the Mg content in the at least one clad layer is about 0.5.
6. The clad sheet product according to claim 1 , wherein the Si content in the at least one clad layer is 0.4-0.6.
7. The clad sheet product according to claim 1 , wherein the Si content in the at least one clad layer is about 0.5.
8. The clad sheet product according to claim 1 , wherein the Mg content in the core layer is 0.5-0.7.
9. The clad sheet product according to claim 1 , wherein the Mg content in the core layer is about 0.6.
10. The clad sheet product according to claim 1 , wherein the Si content in the core layer is 0.5-0.7.
11. The clad sheet product according to claim 1 , wherein the Si content in the core layer is about 0.6.
12. The clad sheet product according to claim 1 , wherein the bending factor, as measured according to ASTM E290, is below 0.3 after 12 months natural ageing.
13. The clad sheet product according to claim 1 , wherein the bending factor, as measured according to ASTM E290, is below 0.25 after 6 months natural ageing.
14. The clad sheet product according to claim 1 , wherein the bending factor, as measured according to ASTM E290, is below 0.25 after 12 months natural ageing.
15. The clad sheet product according to claim 1 , wherein the paint bake response is greater than 75 MPa.
16. The clad sheet product according to claim 1 , wherein the product is for use in an automotive structure.
17. The clad sheet product according to claim 16 , wherein the automotive structure is a panel or a hood.