Ongoing weight reduction efforts have driven a steady decrease in the thickness and mass of automotive components in recent years. That’s why U. S. Steel has developed new grades of steel to resist the tendency of thin-gauge exposed panels to permanently dent, the result of anything from a hail storm to stones thrown off a construction vehicle, an errant baseball throw to an out-of-control shopping cart.

Dent-resistant steels from U. S. Steel offer a combination of formability and high yield strength that is not attainable with low-carbon, mild steels or conventional high-strength steels—these are advanced, bake-hardenable steels designed to have the formability requirements needed in most exterior applications.

Dent-Resistant Steel Product

Bake-Hardenable Steels 180 | 210 | 240

FEATURES

A bake-hardenable steel is any steel with the capacity for a significant increase in strength through the combination of work hardening during part formation and strain aging during a subsequent thermal cycle such as a paint-baking operation.

A combination of relatively low yield strength prior to manufacturing and high in-part strength after forming and paint baking makes bake-hardenable steels ideal for applications where dent and palm printing resistance is important. This material can be used in relatively complex deep draw or stretching operations. High in-part strength also makes bake-hardenable parts good candidates for downgauging to reduce weight.

In bake-hardenable steel, the amount of strain introduced during the forming process will largely dictate the final strength of the part. Since automotive parts—specifically exposed body panels—have a wide array of designs, there will be a corresponding disparity in the amount of strain introduced in these varying geometries. As a result, when using bake-hardenable steel, it’s important to design an adequate amount of strain into a part in order to fully utilize this material’s dent-resistant characteristics.