World’s First 2GPa Steel
South Korea’s leading steelmaker POSCO said on Jan. 10 that it is showcasing its automotive steel technology and 30 types of futuristic car components to be used in next-generation cars for the first time in the industry at this year’s North American International Auto Show (NAIAS) taking place in Detroit, Michigan, from Jan. 11 to 24 (local time).
The steelmaker is presenting mainly its self-developed advanced automotive steel technologies, including TWIP and hot press forming (HPF) steel with upgraded strength and elasticity compared to existing products, at the auto show.
TWIP steel is able to withstand up to 100 kilograms per square millimeter and boasts up to five times higher formability, the ability of sheet metal to be formed into a desired shape without nicking or cracking, compared to its conventional counterparts. Boasting heightened applicability, strength and shock absorption capacity, TWIP steel can be applied to the front and back bumpers of vehicles, significantly improving safety. Until now, many rival steel makers have been working on the material but failed to produce it commercially.
Moreover, it is hard to process HPF steel when it has a tensile strength higher than 1.5 GPa, which can usually withstand up to 150 kilograms per square millimeter, but the company made up for the weakness. The product will be used in the center pillars, which protect passengers from external shocks in broadside collisions and rollover accidents. Currently, POSCO is the only company in the world that has succeeded in producing a product with the tensile strength of the world’s highest level of 2 GPa. This product was first used in Renault’s EOLAB Concept Car powered by a 1.0-litre engine, which made its first debut at the Paris Motor show in 2014, earning favorable reviews.
POSCO will also reveal the PosM-XF, a next-generation TWIP with improved forming ability, together with the recently developed 1 GPa TRIP steel.
A POSCO official said, “The automotive body is 26.4 percent lighter but safer than conventional steel frames of mid-sized sedans. It has received a ‘Five-Star’ rating in European New Car Assessment Program tests and a ‘Good’ rating in the U.S.’ Insurance Institute for Highway Safety (IIHS) tests.”
In particular, this automotive body emitted 50 percent less carbon dioxide than conventional steel frames of cars with internal combustion engines and 9 percent less carbon dioxide than conventional steel frames of electric vehicles with the same size at the Life Cycle Assessment (LCA), which measures carbon dioxide emissions from material production to recycling.