New technical solutions to achieve high-precision molding of flangeless automotive parts

Japan’s JFE Steel Corporation recently announced that it has signed a cross-license agreement (Cross-License) with Germany’s ThyssenKrupp Steel Europe for the new forming technology of steel sheets for automotive parts. The two companies combine their own unique technologies to provide automotive companies with a new forming technology solution, which is to process and manufacture automotive parts without flanges (welded parts) from a single steel plate. With this new technology, the weight of components can be reduced by more than 10%. As a result, both companies have strengthened their ability to use new high-strength steel sheet forming technology to meet the needs of automotive lightweighting. The above-mentioned agreement is signed until July 2021 for a period of 5 years.

Since 2002, JFE Steel Corporation and ThyssenKrupp have signed a package of technical cooperation agreements on the research and development of high-strength steel sheets for automobiles. This technical exchange agreement has been negotiated since the summer of 2012. According to the agreement, JFE Steel will provide its forming technology “CP-F” (Cl osed Prof il e-Forming), provided by ThyssenKrupp Steel Europe Molding technology “T3” (Thyssenkrupp Tai l ored Tubes).

The new molding technology, which combines the technologies provided by the two companies, is mainly aimed at the processing and manufacturing of automobile frame components such as front pillars. The new technical solution is suitable for high-strength steel. In the future, the two companies will provide specific process plans based on the needs of Japanese and European and American automobile companies, combined with the performance of the steel plate.

Generally speaking, car frame parts are produced by spot welding of two stamped and formed steel plates. Using new technology, the flange can be omitted, a steel plate is formed, and continuous welding methods such as laser welding are used for production. Owing to the omission of the flange, it can be made rigid and impact safe, and the weight of the component can be reduced by more than 10%.

The two companies have been developing their own molding technology for flangeless parts. JFE Steel Corporation developed the closed section forming technology “CPF” in 2010. Although this technology can be formed using a general-purpose press, it has a problem of poor dimensional accuracy and stability when forming parts that are bent in the longitudinal direction such as the front pillar. The “T3” technology developed by ThyssenKrupp Europe is characterized by the use of a special mold called “Fl exibl e Mandrel” for molding, which can ensure high precision even for parts that are curved in the length direction. By combining these two technologies, a general-purpose press can be used to stably mass-produce flangeless parts that are curved in the longitudinal direction, lightweight, and highly accurate.

Since the two companies concluded a technical cooperation agreement for automotive steel sheets in 2002, they have carried out the unification of high-strength steel production specifications, the provision of production technologies such as JFE high-lubricity coated steel sheets for automobile outer panels, and the production of 780MPa hot-rolled high-strength steel. Joint development and other projects. In the future, the two parties will continue to promote technical exchanges and joint research and development related to automotive steel sheets and their utilization technologies.