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Use of ULSAB Technologies by Automakers Growing Rapidly

16 February 2000

American Iron and Steel Institute: Use of ULSAB Technologies by Automakers Growing Rapidly
          Applications of High Strength Steel, Tailor Welded Blanks,
                  Hydroforming and Laser Welding All Are Up

    DETROIT, Feb. 16 -- In the nearly two years since the global
steel industry unveiled its UltraLight Steel Auto Body (ULSAB), the world's
automakers steadily have been increasing their uses of the advanced steel
technologies that ULSAB demonstrated so effectively.
    The primary ULSAB technologies that have been showing up in new vehicles
include high and ultra high strength steel, tailor welded blanks, hydroforming
and laser welding.
    "Car companies don't want to tip their hands so it has been difficult for
us to learn in advance exactly how our customers are applying ULSAB
technologies," said Darryl C. Martin, senior director, Automotive
Applications, American Iron and Steel Institute (AISI).  "But, we know they
are.  We see abundant examples of these technologies in the vehicles they have
put on the road since we unveiled ULSAB in March 1998.  The feedback we have
received -- both formal and informal -- has been very encouraging," said
    ULSAB demonstrated that through the use of advanced steels, the latest in
process technologies and holistic engineering, it is possible to substantially
reduce the mass of body structures using steel.  Doing so helps vehicle makers
gain all the numerous benefits of steel including safety, low cost and
environmental friendliness, while reducing emissions and increasing fuel

    High Strength Steel -- Fastest Growing Automotive Light Weighting Material
    ULSAB used more than 90 percent high strength and ultra high strength
steels, which played a significant role in reducing body weight while
providing excellent crash performance.  Examples of current vehicles using
high amounts of high strength steel include:
    *  The 1999 BMW 3-series has a body structure weighing 230 kg with a high
strength steel content of 50 percent.  The previous model contained less than
5 percent.
    *  Ford's new Focus uses high strength steel for both the body structure
and exterior body panels.
    *  The new Mercedes Benz S-Class uses 38 percent high strength steel,
which contributes to lower body weight, an increase in torsional stiffness of
70 percent and improved crash performance.
    *  Toyota's latest sub-compact car, Vitz, uses high-strength steel in 48
percent of the mass of its 253-kg body-in-white, which weighs 17 kg less than
its predecessor, the Starlet.
    *  Ford's Windstar utilizes almost 60 percent high strength steel.

    Tailor Welded Blanks Save Weight, Cost
    ULSAB pushed the envelope by using 14 tailor welded blanks, representing
45 percent of the body structure mass.
    *  The new GM "G" platform (Cadillac DeVille, Buick LeSabre, Pontiac
Bonneville and Oldsmobile Aurora) uses a tailor welded blank for the body side
inner panel, similar to a body side outer panel used in ULSAB.  Use of a
tailor welded blank for the body side outer in ULSAB added an extra challenge
to the project because the rear quarter panel is a visual part.
    *  The GM "G" platform also employs North America's first non-linear
tailor welded blank applications in the floor pan.
    *  The Volkswagen Golf, the car with the highest number of tailored
blanks, employs 14 to 21 tailored blank parts, depending on the specific
    *  GM's 2000 full size SUVs incorporate finished blanks that measure 103
in. by nearly 71 in., the largest tailored units that the company has ever
    *  Nearly all Chrysler platforms now use tailor welded blanks.  The Jeep
Grand Cherokee uses nine, four of which are in the body structure.
    *  The most common use for tailored blanks is the door inner panel:  the
new BMW 3-series (with a diagonal running weld line), Mercedes S-Class, 2001
Ford Explorer, Dodge Durango, Chrysler LH platform, Jeep Grand Cherokee, Honda
Accord, Dodge/Plymouth Neon, PT Cruiser, Cadillac Seville and VW Golf.

    Hydroforming Use Grows
    ULSAB demonstrated an innovative, hydroformed side roof rail that runs
from the A-pillar along the B- and C-pillars into the rear floor panel.  It is
a key element in the structure and provides an excellent load path for
structural stiffness and performance in crash.  Instead of using a standard
tube with a relatively low diameter to thickness ratio (D/t), the ULSAB
hydroformed roof rail is constructed from a tube with a diameter of 96 mm and
a thickness of 1 mm, resulting in a D/t ratio of 96.
    *  GM has been using hydroforming for a similar roof rail application as
ULSAB in the body structure of such vehicles as the Buick Park Avenue and
Cadillac Seville.  Size and location of the roof rail are different than in
ULSAB in that the tubes GM is using are much thicker gauge.
    *  GM also is using this technology for the front part of the main frame
members for the Sierra/Silverado trucks.

    Currently, the main application for hydroforming is in engine cradles,
suspension, radiator supports and IP beams, but carmakers are using more
hydroforming in the body-in-white.  At the 1999 International Body Engineering
Conference (IBEC), Rover presented a paper on a hydroformed space frame
concept for the Land Rover Freelander.  Rover initiated the project after
assessing ULSAB and plans to demonstrate additional innovative hydroforming
for main body structure members.

    Laser Welding
    The ULSAB body structure features 18 m of laser welding, approximately 60
percent of which is required to join the hydroformed side roof rails to the
roof.  This approach accommodates one-sided access and enhances the stiffness
of the body-in-white.
    *  Volvo began using laser welding for the roof in the 850 (the
predecessor of the V70), followed by other European automakers including BMW,
Volkswagen and Mercedes.

    ULSAB extended the use of laser welding to the upper and lower front rails
to enhance crash performance, over an alternative design using standard spot
welding.  Instead of using thicker, heavier material, Porsche Engineering
Services elected the innovative approach of employing laser welding, resulting
in a stronger, continuous joint.
    The American Iron and Steel Institute (AISI) is a non-profit association
of North American companies engaged in the iron and steel industry.  The
Institute is comprised of 46 member companies, including integrated and
electric furnace steelmakers, and 175 associate and affiliate members who are
suppliers to or customers of the steel industry.  For more news about steel
and its applications, view American Iron and Steel Institute's website at .
    The Automotive Applications Committee (AAC) is a subcommittee of the
Market Development Committee of AISI and focuses on advancing the use of steel
in the highly competitive automotive market.  With offices and staff located
in Detroit, cooperation between the automobile and steel industries has been
significant to its success.  This industry cooperation resulted in the
formation of the Auto/Steel Partnership, a consortium of DaimlerChrysler, Ford
and General Motors and the member companies of the AAC.
    This release and other steel-related information are available for viewing
and downloading at American Iron and Steel Institute/Automotive Applications
Committee's website at

             Automotive Applications Committee member companies:
                             AK Steel Corporation
                         Bethlehem Steel Corporation
                                 Dofasco Inc.
                              Ispat Inland, Inc.
                              LTV Steel Company
                          National Steel Corporation
                             Rouge Steel Company
                                 Stelco Inc.
                  US Steel Group, a unit of USX Corporation
                               WCI Steel, Inc.
                          Weirton Steel Corporation