This article discusses the results of FutureSteelVehicle (FSV), a three-year program of WorldAutoSteel to create fully engineered, steel-intensive designs for electric vehicles which have reduced lifetime greenhouse gas emissions.
The FSV program created optimized advanced high-strength steel (AHSS) body structures for four future 2015-2020 model-year vehicle: PHEV and fuel cell (FCEV) C-/D-Class vehicles; and battery electric (BEV) and plug-in hybrid electric (PHEV) A-/B-Class vehicles.
The results demonstrated that the steel body structure designs are able to reduce mass by over 35% when compared to a benchmark vehicle and minimize lifetime emissions by roughly 70%, while fulfilling a large number of global crash and durability specifications, facilitating five-star safety ratings, and eliminating pricey penalties for mass reduction.
FSV Material Portfolio
The FSV program expanded its portfolio by bringing in more sophisticated more advanced steel and steel technologies, which include over 20 new AHSS grades that represent materials anticipated to be available in the market in the 2015-2020 technology horizon.
The FSV material portfolio included hot formed (HF), complex phase (CP), twinning-induced plasticity (TWIP), transformation-induced plasticity (TRIP), and dual phase (DP) steels, which achieve GigaPascal-strength levels and are the latest in steel technology provided by the global steel industry.
The design flexibility of steel enables it to leverage the design optimization process which produces innovative solutions for structural performance. The resulting optimized component configurations and shapes often replicate the design efficiency of Mother Nature. FSV’s steel portfolio is used during the process of material selection with the help of full vehicle analysis to identify material grade and thickness optimization.
As a result, the FSV concepts are very light weight and highly efficient. The weight of FSV’s A-/ B-Class PHEV20 vehicle is 175 kg, where as that of the larger C-/D-Class vehicle versions is 201 kg. The weight of FSV’s BEV concept is 188 kg, which is over 35% lesser than a baseline ICE body structure modified for a battery electric powertrain and regulatory requirements of year 2020.
Non-Intuitive FSV Structures
Non-intuitive structures can be found throughout the FSV structures. The following are the selected examples:
It is fabricated with roll-formed CP steels of GigaPascal strength. The rocker looks like a skeletal bone, providing outstanding results in four various side crash simulations that cover a broad list of global specifications.
Shot Gun Sub-System
It looks like a shot gun-type rifle, delivering very high performance in both full frontal and offset crash simulations. The Shot Gun consists of a three-piece HF steel custom welded blank of different thicknesses, fabricated utilizing hot stamping with custom quenching.
Front Rail Sub-System
It is a new design for automotive front crash structures. The rail’s unusual section shape was the outcome of the design optimization approach that optimized the efficacy of each steel material to obtain minimum mass and better crash management performance. It is fabricated with varying gauges of TRIP material using a laser welded blank.
The design optimization process included crash analyses that are a combination of the most stringent global specifications. FSV fulfills or surpasses the structural specifications, and hence facilitates the achievement of five-star safety ratings in final production vehicles.
Life Cycle Assessment Approach
A life cycle assessment approach helps automotive manufacturers in assessing and minimizing the total energy consumption and the lifetime greenhouse gas emissions of their vehicles. Regulations focusing only on the vehicle use phase promote the use of low-density, greenhouse gas-intensive materials, which may provide lighter weight parts that enhance fuel economy and tailpipe emissions in some applications. Nevertheless, it may result in increased greenhouse gas emissions during the total life cycle of the vehicle. Life cycle assessment comparison between the US and Europe energy grids is shown in the following table:
Life Cycle Assessment Comparison Between U.S. and Europe Energy Grids
||Material & Recycling (kg CO2e)
||Use Phase (kg CO2e)
||Total Life Cycle (kg CO2e)
|Polo V ICEg
|FSV BEV USA grid
|FSV BEV Europe grid
|FSV vs. Polo V - USA grid
||- 56% CO2e reduction
|FSV vs. Polo V – Europe grid
||- 68% CO2e reduction
The lightweighting capabilities of the new steels make steel is the material of choice for achieving reductions in all life cycle phases. As the automotive industry’s measures to minimize carbon dioxide equivalent emissions focus more on sophisticated fuel sources and powertrains, material production will represent a much larger percentage of total life cycle emissions. The FSV program is the latest inclusion to the series of measures taken by the global steel industry to provide steel solutions to address the challenges being faced by automakers worldwide to achieve increased fuel efficiency, reduced greenhouse gas emissions, improved performance and safety without compromising affordability. This program is in line with the ULSAB-AVC (Advanced Vehicle Concepts) 2001, UltraLight Steel Auto Suspension 2000, UltraLight Steel Auto Closures 2000, and UltraLight Steel Auto Body 1998, accounting for roughly €60 million in research and demonstration investment.
This information has been sourced, reviewed and adapted from materials provided by WorldAutoSteel (World Auto Steel).
For more information on this source, please visit WorldAutoSteel (World Auto Steel).