Look around your shop, and you’ll likely see an old, transformer-based spot, MIG or MAG welder. Every facility has at least one, and many of these welders have been in service for years, if not decades. If it has lasted this long, there’s no rush to replace an old welder, right?
Car and truck body design is evolving rapidly, driving advancements in welding technology. Welders that have limited, all-manual inputs and no feedback for the operator are now facing competition from automatic setting transformer welder as vehicle manufacturers increase their use of advanced high-strength steels and aluminum. These metals react very differently than traditional steel when welded. To repair the vehicles of today and the future, you will have to continually maintain your welding training to ensure you can properly work with modern materials and those to come.
Understanding advanced high-strength steel and aluminum
OEMs are using a variety of strategies to boost the fuel efficiency of their vehicles. One way to limit fuel consumption is by making the vehicle body lighter through the use of two groups of metals: advanced high-strength steels and aluminum alloys.
Advanced high-strength steels include a variety of steels with tensile strengths ranging from 550 MegaPascals (MPa) to 2,000 MPa. These are significantly stronger than traditional “mild” steels, enabling OEMs to design thinner, lighter structural pieces and panels. Automakers also save weight by replacing steel components with aluminum ones. Today’s aluminum alloys have tensile strengths similar to mild steel, but weigh up to 40 percent less.
According to a Ducker Worldwide study, North American vehicle manufacturers nearly doubled their use of advanced high-strength steels between 2005 and 2009, and are expected to more than double it again by 2025. A separate Ducker study predicts that North American OEM demand for aluminum will grow from less than 200 million pounds in 2012 to nearly 4 billion pounds in 2025.
As the vehicle body becomes lighter in the coming decades, it will also become more diverse. That’s because automakers can pick and choose from an array of advanced high-strength steels and aluminum alloys, each with its own strength and weight characteristics. Some of these metals are ideal for crumple zones or structural pieces, while others are more suited for body panels and closures.