The alloy could serve as a cost-competitive alternative against traditional 7xxx-series aluminum alloys starting from 2017.
High-strength aluminum solutions are becoming increasingly important for an automotive industry that is using light metals in greater quantities to build safer and more durable vehicles, specifically to meet stricter fuel efficiency regulations coming into effect. Aluminum can provide substantial savings in weight compared to steel components. With its unique qualities, aluminum extrusions can absorb twice the amount of crash-induced energy as the heavier metal.
Sapa has worked to develop the new 6xxx-series alloy to meet the need for ultra high-strength alloys in the automotive market. Automotive suppliers currently specify high-strength alloys for structural applications that have elevated strength requirements, like bumper systems, crash boxes and side sills.
Such applications typically utilize 7xxx-series alloys, which are relatively expensive and more difficult to extrude on a production level than those in the 6xxx family. The new alloy that Sapa is developing can achieve similar yield strengths, but with better extrudability than the 7xxx alloys.
Standard 6xxx alloys on the market today typically do not exceed tensile yield strengths above 320-330 MPa. The new alloy has been outperforming these standards with yield strength above 350 MPa and 10 percent elongation.
Sapa has already established the alloy in terms of the most promising composition range. The next step is optimizing the alloy in production, says director of metallurgy David Lukasak of Sapa. “We still have a fair bit of work to ensure manufacturing and commercial success. And we are confident that the industry is going to recognize this as a positive step forward,” he says.
Simon Jones of Sapa Technology Americas adds that material research, including chemical expertise, is one of the company’s key competence areas. “We develop material that can meet the needs of different applications. It is part of our commitment to the customer,” says Jones.