Aluminum alloy for car door
is formed by extrusion of 6005 6005A aluminium alloy
. It belongs to Al-Mg-Si-Mn-Cr alloy. It can be strengthened by heat treatment. The main strengthening phase is Mg2Si. Increasing Mg and Si content can increase the strength of 6005 6005A aluminium alloy,
but the content of Mg2Si is too large to form more Mg2Si particles, and the quenching sensitivity should be increased. With the increase of quenching speed and strength, the bending and extrusion properties of profiles become worse, and there are too many extrusion stripes on the surface of profiles. Therefore, 6005 aluminium alloy
should be used to make car doors, without Mn and Cr, while 6005A aluminium alloy
(Mn+Cr) content is 0.12%~0.5%.
Production process of aluminium alloy profile for 6005 aluminium alloy car door
Chemical composition (mass fraction): Si 0.65-0.8, Mg 0.5-0.6, Fe 0.3, Cu, Mn, Cr, Zn are less than 0.05, 0.03 < Ti < 0.1, the rest are Al;
Casting temperature: 710-720 C, casting speed 105mm/min, cooling water pressure 0.08N/mm_;
The extrusion process parameters are as follows: heating temperature of ingot 500-520 C, extrusion speed 10-15m/min, extrusion temperature of profile 525-535 C.
The mechanical properties of 6005 aluminium alloy
are as follows: