Joint effort by Chinalco Institute of Materials and Southwest Aluminum enables localised production of 6XXX aluminium alloy sheet

Chinalco Institute of Materials and Southwest Aluminum have collaboratively developed a novel 6XXX aluminium alloy sheet. This new sheet, designed for automobile panels, features exceptional formability and superior surface quality.

The 6XXX aluminium alloy sheet has passed batch verification for use in automobile tail cover inner panels and door inner panels by a leading Shanghai-based automotive manufacturer. This marks the beginning of its supply, paving the way for localised production of 6XXX aluminium alloy for panel inner panels.

About the collaboration

The Chinalco Institute of Materials and Southwest Aluminum have collaborated to address key challenges and successfully developed a high-formability, high-surface 6XXX aluminium alloy for automobile panels specifically designed for inner panels.

This alloy boasts low yield strength, excellent stamping formability, high baking paint strength, and stable performance at room temperature. Importantly, it meets the stringent requirements for both inner and outer panels of automotive bodies.

The alloy has not only successfully undergone trial stamping for the inner panels of tail covers and front/rear doors at a prominent Shanghai-based OEM but has also passed batch certification. This marks a significant milestone in import substitution efforts and should instill confidence in the new alloy's performance.

The shift to 6XXX aluminium alloy

Traditionally, 6XXX aluminium alloy is used for outer automobile panels, while 5XXX aluminium alloy is preferred for inner panels. However, this approach poses challenges for resource recycling. Shifting from 5XXX to 6XXX aluminium alloy for inner panels aligns better with green and low-carbon development goals.

Due to their complex shapes, the inner panels require high formability, and the 6XXX alloys used so far have been imported, leading to high costs and long delivery times. Therefore, there is a pressing need to develop domestic 6XXX aluminium alloy plates to replace imported ones.