Reinvention of Steel Could Make Car Bodies 30% Lighter - Nippon Steel
Bloomberg reported that Nippon Steel Corp is pushing the envelope in order to stay relevant as the auto industry, its most important customer, goes through major changes. Steel has been the main material in cars since Henry Ford started mass producing them a century ago. But the heavy metal is falling out of favor because automakers can’t meet new fuel efficiency standards or build long-range battery-powered cars without shedding precious pounds. Several years ago, Ford Motor Co decided to build its best-selling F-150 pickup truck mostly out of aluminum and steelmakers have been panicking ever since. That’s why Nippon Steel last April opened a research department to come up with tricks for making car parts lighter, using super-advanced grades of the material it’s been smelting for 118 years. In January, the firm unveiled the results of the new approach: an all-steel car body, built in house, which it says cuts weight by 30%, putting it on par with aluminum.
Nippon Steel’s laboratory research head Mr Nobuhiro Fujita said that “There’s this idea out there that steel is an old-fashioned material, but it’s not true.”
The car body it exhibited at a Tokyo trade fair in January cuts weight by 30% using a half-dozen different grades of the metal. The strongest has a tensile strength of 2,000 mega pascals, which means it can withstand 290,000 pounds of pressure per square inch several times more than the advanced steel commonly used in cars today without breaking. Nippon Steel’s engineers also found ways to redesign components so they could be made with less material. For example, they used a combination of thinner body panels and reinforcement bars to shave 20% off the weight of door modules, without sacrificing strength. The next goal is to prove that high-grade steel can be used to cut the weight of car bodies by half. That may require some compromise, though, since steel can only get so strong or light. To push the limits, Nippon Steel is experimenting by mixing small amounts of plastics with the metal it’s been producing for decades.
For years, cars have actually been gaining weight, not losing it, adding about 400 kg in the last two decades alone, according to automotive consultancy A2Mac1. Beefier beams and pillars for added crash protection and more amenities like power seats have been the main culprits, along with popularity of behemoth pickup trucks and SUVs. Now tighter emissions rules are forcing manufacturers to consider dieting. The pressure will only increase as automakers produce more electric cars because batteries aren’t powerful enough to carry extra weight and still propel cars for long distances. Mr Akihito Fujita, a New York-based consultant at Nomura Research Institute America Inc, said “Over time, this will mean more aluminum, more exotic materials like carbon fiber and magnesium and less steel. By 2025, steel will account for only 62% of the weight of the average new vehicle, down from 70% in 2015. The move away from steel is inevitable.”
Source : Bloomberg