6xxx series aluminium alloy sheets or blanks with improved formability

Process for producing a sheet or a blank, comprising the following in succession:

• (a) casting a 6xxx alloy comprising, in wt. %:
• Si:
• 1.25-1.45
• Fe:
• <0.30
• Cu:
• <0.15
• Mn:
• 0.01-0.18
• Mg:
• 0.25-0.40
• Cr:
• <0.03
• Ni:
• <0.04
• Zn:
• <0.15
• Ti:
• 0.01-0.10
• other elements:
• <0.05 each and <0.15 in total
• rest aluminium;
• (b) heat treating;
• (c) hot rolling;
• (d) cold rolling;
• (e) optionally inter-annealing between hot rolling and cold rolling and/or during cold rolling and/or after cold rolling;
• (f) solution heat treating;
• (g) quenching;
• (h) optionally pre-aging;
• (i) shearing without any milling
• wherein a sheet temperature at a beginning of the quenching is from 480 to 570° C. and optionally, the sheet temperature at an end of the quenching is from 50 to 160° C.

A 6xxx alloy comprising, in wt. %:

• Si:
• 1.25-1.45
• Fe:
• ≤0.30
• Cu:
• ≤0.15
• Mn:
• 0.01-0.15
• Mg:
• 0.25-0.40
• Cr:
• ≤0.03
• Ni:
• ≤0.04
• Zn:
• ≤0.15
• Ti:
• 0.01-0.10