Each Mg cross-form stamping, created for the Mg sheet demonstration project, is an 18-by-18-in. square that incorporates both stretch and draw-depth characteristics. (USCAR/USAMP)

USCAR broadens its research footprint

Lightweight materials, advanced propulsion, data management and net-zero carbon reduction top the list of collaborative projects now underway.

The project teams working under the USCAR (United States Council for Automotive Research) umbrella help carve a knowledge pathway to accelerate technology development. “We typically have approximately 60 teams working on USCAR projects that involve more than 600 experts from our member companies,” Steve Zimmer, USCAR executive director, told Automotive Engineering. “At any given time, we have roughly 100 active projects.”

Founded in 1992, USCAR is a collaborative hub for research and other pre-competitive activities. The organization’s technical focus areas include materials, electronics/electrical, manufacturing, energy storage, and advanced propulsion. Commercialization is the independent responsibility of each member company: Fiat Chrysler Automobiles (FCA) US, Ford Motor Co. and General Motors. To underscore the ongoing work of USCAR and its subsidiaries, the following highlights ongoing projects and a future endeavor:

A material difference
As a lightweighting asset, magnesium (Mg) trails its steel and aluminum counterparts in vehicle applications. Recent Mg production die castings include the rear swing gate on the Jeep Wrangler, the Chevrolet Corvette Stingray’s belt-line reinforcement, the front suspension strut brace on the Ford Mustang GT500 and the Chrysler Pacifica’s lift-gate inner panel.

“Although there have been a few large cast Mg parts used by OEMs on vehicles, there are currently no Mg sheet parts on production vehicles,” noted Randy Gerken, FCA’s Mg sheet project team representative. Creating a viable pathway for Mg sheet parts is the focus of a current USAMP (United States Automotive Materials Partnership) project.

The USAMP subgroup includes six automotive tier suppliers, five universities, two national labs, and six technology vendors. Its Mg project team looked at numerous Mg-scripted studies, including rolling trials on experimental alloy ingots, pretreatment and corrosion coatings, lubricants as well as forming and joining techniques.

“While extensive evaluations of three experimental Mg alloys are ongoing along with integrated computational materials engineering of newer alloy candidates, the team has selected one novel Mg alloy variant for detailed characterization, testing, sheet component development, coating evaluations and stamping demonstration,” explained Gerken.

As the project draws closer to its targeted May 2021 conclusion, the Mg team will use a cross-form stamping process on an intermediate-sized model part to test the material models and finite element analysis material cards developed for the selected Mg alloy. Although not a production part, the cross-formed model part has similar draw-depth and stretch characteristics, providing a sufficient test of the forming simulations, according to Gerken.

The USAMP simulations and forming experiments are the prelude to producing Mg closure panels in 1.2 mm/0.047 in. thickness. Based on the 2013 Ford Fusion midsize sedan’s steel inner and outer panels, the project team’s Mg door inner and outer panels will be produced by a warm-forming process. For Mg, the warm forming process unfolds in the 250-350°C range, occasionally at higher temperatures. “One of the USAMP’s key project objectives is to drive down the warm forming temperature to 200-degrees C with innovative alloying and forming process conditions,” Gerken explained.

When compared to steel- or aluminum-sheet panels, the sole advantage of using Mg sheet is to reduce vehicle mass, enabling lower emissions and fuel consumption, according to Gerken. The 42-month project’s end-game is a Mg manufacturing cost of less than $2.50 per pound of weight saved.

Faster EV battery charging
With the U.S. Department of Energy (DoE) reporting the average electric vehicle (EV) battery cost at $185/kWh in 2019, the pursuit of low cost (the industry target is $100/kWh), fast charge batteries continues. USCAR’s Advanced Battery Consortium (USABC) awarded separate contracts to Zenlabs Energy, Inc. and the Worcester Polytechnic Institute (WPI) in 2019 and 2020 respectively. USABC’s WPI program is primarily focused on multi-layer structured electrode dry coating technology. A lower cost is expected with dry coating technology versus a conventional slurry due to the absence of a solvent.

Fremont, California-based Zenlabs’ development targets include the creation of a new electrolyte formulation enabling new negative electrode materials to lower the cost. Another USABC contract in 2020 went to Stafford, Texas-based Microvast, Inc., to develop an automotive lithium-ion pouch cell capable of achieving a 15-minute fast charge.

“Battery charging times today are typically 30-45 minutes, under fast charging conditions, although not all of the charge-time limitations are attributed to the EV cells,” said Mark Verbrugge, GM’s representative to the USABC management committee. The three advanced-batter contracts as well as a technical assessment program with Andover, Massachusetts-based Physical Sciences, Inc., underscore the not-a-single-solution reality of battery development.

“New electrode materials, novel electrolyte formulation, specific cell design, unique electrode structures and many other factors may all have an impact on the fast charging capability and cost,” explained Verbrugge. Current EV batteries typically have a relatively thick coating on the electrode. And a thick coating means both ion and electron transfers are slower, essentially hindering a fast charge capability. “There are many ways to improve the conductivity, but at the same time the battery production cost may be increased,” he said, underscoring the challenge to achieve fast charging at a double-digit-percentage cost reduction.

Data and more data
High-speed connector speeds streamline the data-exchange needs of infotainment systems, driver assist systems, cameras and other vehicle systems. “Companies have been developing high performance data connectors, but there is no requirement for the connectors to work together,” said Greg Shanahan, GM representative to the consortium’s Electrical Wiring Component Applications Partnership (EWCAP). After completing projects for high-speed data connectors and high-performance miniature coaxial connectors, the EWCAP team will conclude its differential pair connectors for an Ethernet project in late 2020.

“The Ethernet program is the most ambitious of the three projects,” Shanahan said. “Ethernet’s very fast data speeds are critical to the success of new vehicles, especially those with automated driving features.” While suppliers and OEMs can design unique differential pair Ethernet connector solutions, the drawbacks are redundant design efforts and an abundance of incompatible parts. The USCAR collaboration results in a shared design interface that “assures interchangeable and interoperable designs,” Shanahan said.

Stomping out the carbon footprint
An August 2019 workshop with attendees from the DoE, the electric utility and energy industries, national labs, and USCAR members planted the seeds for the Net-Zero Carbon Fuel Project. Over the next three years, the parties expect to agree on cost effective ways to create fuel that will burn with a net zero carbon footprint.

“Because of the large number of potential pathways and the analysis needed to fairly assess them, it will take time to provide assurance to all parties that the most effective and economical solutions have been found and warrant major investment,” said Jim Anderson, Ford representative to the Net Zero Carbon Fuel Project.

Every type of vehicle, including aero and marine, currently powered by some form of hydrocarbon fuel, and all transportation modes are in the loop for a net-zero carbon fuel equation. Once the Net Zero Carbon Fuel project team agrees on the pathways, the next step will be a pilot project to demonstrate useable net zero carbon fuel for the transportation industries. “We will need a diversity of solutions – on and off the vehicle,” Anderson said, adding, “USCAR is focused on developing the necessary learnings.”

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