Products and solutions, 2000-03-20, 01:00 AM
Steel segment: High-strength dual-phase steel used for first time in auto body panels
With immediate effect Ford-Werke AG is using the high-strength dual-phase steel DP-K 30/50 from Thyssen Krupp Stahl AG for the door outer panels of the Ford Puma. The Cologne, Germany-based company is the world´s first auto manufacturer to use a steel of this strength for the volume production of body panels, achieving further weight reductions and benefiting from improved component properties. The application also demonstrates that high-strength dual-phase steel in the form of cold strip satisfies the highest requirements, also for surface quality.
The use of DP-K 30/50 with a tensile strength of 500 newtons per square millimeter allows the sheet gauge to be reduced without sacrificing functionality. Compared to the bake-hardening steel previously used by Ford component weight can be reduced by around ten percent. In addition DP-K30/50 offers superior dent resistance.
The microstructure of dual-phase steels comprises 75 to 90 percent soft ferrite and 5 to 25 percent hard martensite. The ferritic structure is interspersed with islands of martensite, providing dual-phase steels with excellent formability and in particular very good stretch forming properties. Thyssen Krupp Stahl AG supplies dual-phase steel sheet in tensile strengths of 500 and 600 newtons per square millimeter. Hot-rolled dual-phase steel is now the number one material in the production of weight-reduced wheels.