Search Results

Advanced high strength steels (AHSS), such as dual phase (DP) and transformation induced plasticity (TRIP) steels, have been used successfully for making light weight vehicles and their usage is growing. Now, the automotive industry is expanding the use of AHSS to higher strength levels for further mass reduction. In a 2003 SAE paper, the material and formability characteristics for such steels were presented for steel grades of DP980, high yield type DP780 (780YM), low yield type DP780 (780YL), TRIP780, and TRIP590. In this study, experiments were conducted to assess the formability of these high strength steels using a T-channel, which incorporates several different forming modes in automotive stamping. The feasibility of computer simulation technology for the formability analyses of AHSS is also addressed.

The remarkable evolution of steel technology in recent years has resulted in the development of new High Strength Steels (HSS) that are increasingly used in today's automobiles. The advanced performance of these grades in ductility and rapid hardening characteristics provides an opportunity to stamp complex geometries with in-panel material strengths far exceeding those of conventional high strength grades of steel. This provides an opportunity to improve an automotive body's performance in crash, durability and strength while reducing the overall weight of the vehicle. An improved understanding of the forming characteristics of these advanced HSS and accurate prediction of the material processing strain will allow vehicle designers to fully explore the opportunities of increased yield, strain hardening, formability and strength and the potential this creates to reduce mass and improve the performance of the automotive body.

Vehicle weight reduction, reduced costs and improved safety performance are the main driving forces behind material selection for automotive applications. High strength steels (HSS) have demonstrated their ability to meet these demands and consequently have been the fastest growing light-weighting material in vehicle structures for the past decade. The evolution in steel technology in recent years has produced new grades of highly formable, advanced high strength steel (AHSS) grades that will continue to meet these automotive demands into the next decade. This paper provides an example of how these advanced automotive materials have been incorporated into the ULSAB-Advance Vehicle Concept (ULSAB-AVC) and how these materials enable cost- and mass-effective solutions that satisfy the increasing crash performance requirements placed on vehicle designs.

Advanced high strength steels (AHSS), such as dual phase (DP) and transformation induced plasticity (TRIP) steels, have been increasingly used in automotive industry. One of the major advantages of AHSS is the excellent crash energy absorption capability. In this study, crash performances were evaluated for four AHSS including DP980, DP780, TRIP780 (780T), and TRIP590 (590T). Axial crush and bending crush tests were performed to evaluate the material crush performance. High strain rate tension test results for those materials were also presented. FEA analyses with parameter sensitivity studies were conducted including strain rate sensitivity effect, part geometry effects, welding models and forming effects. Good correlations between simulation and experimental data were achieved.