EXTRUDED PRODUCT MADE FROM ALUMINIUM ALLOY AL-MG-SI WITH IMPROVED RESISTANCE TO CORROSION

摘要

The invention relates to an extruded product, particularly a drawn tube made from an alloy of the 6XXX series with the following composition (%, by weight) : Mg: 0.4 - 0.7, Si: 0.4 - 0.7, Fe: 0.1 - 0.3, Zn: 0.16 - 0.3, Ti: 0.12 - 0.3, Mn < 0.10, Cu < 0.05, Cr < 0.05, Ni < 0.05. others <0.05 each and <0.15 in total, remainder being aluminium, in which the ratio Si / Mg is between 0.9 and 1.3. Said product offers an advantageous combination of good mechanical properties at operating temperatures for vehicle air-conditioning systems using CO2 as refrigerant fluid and high resistance to perforating corrosion necessary for extended operating life without leaks. Said tubes are advantageously used for cabin air-conditioning systems in motor vehicles using CO2 as refrigerant gas.