Wrought Alloys - 6xxx Al-Mg-Si Alloys
- Heat treatable
- High corrosion resistance, excellent extrudibility;moderate strength
- Building & construction,highway, automotive, marine applications
- Representative alloys: 6061,6063, 6111
- Typical ultimate tensile strength range:18-58 ksi
They are readily welded. A unique feature is their extrudability, making them the first choice for architectural and structural members where unusual or particularly strength- or stiffness-criticality is important.
Alloy 6063 is perhaps the most widely used because of its extrudability; it was a key in the recent all-aluminium bridge structure erected in only a few days in Foresmo,Norway, and is the choice for the Audi automotive space frame members.
Higher strength 6061 alloy finds broad use in welded structural members such as truck and marine frames, railroad cars, and pipelines. Among specialty alloys in the series: 6066-T6, with high strength for forgings; 6111 for automotive body panels with high dent resistance and 6101and 6201 for high strength electrical bus and electrical conductor wire, respectively.
Among the most important applications for Al-Mg-Si alloys are:
- The power of extruded Al-Mg-Si alloys is the "put-the-metal where- you need-it" flexibility that these alloys and the extrusion process provide.
- Roof structures for arenas and gymnasiums are usually 6063 or 6061 extruded tube, covered with 5xxx alloy sheet.
- Geodesic domes,such as this one made originally to house the "spruce Goose" in Long Beach, CA, the largest geodesic dome ever constructed, at 1000 ft across, 400 ft. high.
- An integrally stiffened bridge deck shape usually produced in 6063,used to produce replacement bridge decks,readily put in the roadway in hours.
- The new Mag-Lev trains in development in Europe and Japan employ bodies with 6061 and 6063 structural members.
- Extruded Al-Mg-Si alloys may make up the entire frame of motorcycles or cars.
- Welded 6063 extrusions combined with 5083 tube make up the front and rear axle bodies for the BMW Model 5.