What is in this article?:
- ArcelorMittal Touts New Ultra-Strong Structural Parts for Vehicles
- MDX 'Perfect Example' of Dual Technology
The steelmaker predicts North American automotive customers alone will adopt more than 4 million, hot-stamped, laser-welded blanks during the next two years.
Stiffener ring combines A-pillar, B-pillar, roof rail and lower frame member.
Automotive aluminum seems to be getting all the headlines lately, but steel suppliers are fighting back by spotlighting innovative forming technologies and advanced high-strength steel grades they say can create stronger, lighter and more crashworthy structures at much lower cost than aluminum.
One of the industry’s showcase examples is what’s Acura luxury division says is the world’s first 1-piece stiffener ring for the driver and front passenger door areas on the ’14 Acura MDX CUV.
Combining the A-pillar, B-pillar, roof rail and lower frame member, the 1-piece door ring replaces multiple parts spot welded together to better manage collision energy.
It significantly increases the ability to absorb and redirect crash energy in front and side impacts, and manage roof loads in the event of a rollover, Acura says.
Blake Zuidema, director-global R&D, automotive product applications for steel supplier ArcelorMittal, says the ring played a key role in enabling the MDX to receive the highest rating for the Insurance Institute for Highway Safety’s small-offset crash test, which is proving to be one of the industry’s most challenging.
“You can see in the crash test virtually no deformation in the door-ring area. The doors were actually able to be opened afterwards,” Zuidema says. And even though the door ring is exceptionally strong, it actually helped the automaker trim 8.8 lbs. (4 kg) from the body structure as well, he says.
The door ring combines two sophisticated steel fabricating technologies, laser-welded tailored blanks and hot stamping, into a new highly advanced process that is becoming an increasingly popular method of creating strong, lightweight steel parts, Zuidema says.
Laser-welded tailored blanks are created by welding together different thicknesses and strengths of steel alloys like a quilt to create parts that are customized for specific applications, thick and strong where they need to be and thin and light in lower-stress areas.
Hot stamping is a process where blanks are heated to very high temperatures to become more malleable and easily formed. The hot blanks then are placed in stamping presses with specially cooled dies to be formed into parts.
When the stamping dies press the metal blanks into complex shapes, the sheet metal cools suddenly and the steel undergoes metallurgical changes that turn it into a much stronger material known as press-hardened steel.
“The press-hardened steels provide some of the highest-strength components that are found in cars today,” Zuidema says.