Quest for lighter vehicles behind move
TOKYO – Kobe Steel has begun to produce steel used in a process called hot-stamping in response to growing demand from automakers for lighter and stronger components. The Japanese steelmaker hopes that the steel will offer carmakers an alternative to high-tensile steel, aluminum and carbon fiber when they seek to save weight in their vehicles. Kobe Steel has started making hot-stamping steel at its works in Kakogawa, Hyogo Prefecture. The company plans to pitch the material, which sports tensile strength of roughly 1,470 megapascals, to various automakers for use in chassis parts. Such parts are already used in Toyota Motor’s highly popular Prius hybrid. In an effort to swiftly meet increasingly challenging fuel efficiency standards around the globe, Japanese automakers have increased the use of high-tensile steel. However, the strength of this type of steel currently comes to about 1,180 megapascals at best. Kobe Steel believes that hot-stamped steel parts can provide similar levels of strength at roughly 10% less weight. Hot-stamped steel components are not as widely used as their high-tensile steel counterparts because a heating furnace is needed for hot stamping. Furthermore, fewer hot-stamped steel parts can be produced in a given time than high-tensile steel components.
Kobe Steel has decided to offer hot-stamping steel because its product makes it possible for parts makers to quadruple output, thanks to its unique composition. Even then, high-tensile steel offers higher productivity, but the company believes that the gap in production costs is now narrow enough to make hot stamping an attractive option.
Nippon Steel & Sumitomo Metal was practically the only Japanese company to offer hot-stamping steel until Kobe Steel’s market entry. The trailblazer is looking to lift its annual hot-stamping steel production capacity at its Yawata plant in Kitakyushu by roughly 20% to around 300,000 tons by the end of the year.
The company’s aluminum-plated hot-stamping steel has been used by European automakers at their Chinese production bases. It expects Japanese carmakers to also start using the material. Nippon Steel will continue to focus on high-tensile products when it comes to developing lighter steel, but it has decided to boost its hot-stamping steel output capacity to meet demand from customers.
And demand for hot-stamping steel in Japan likely will increase further in the near future. Gestamp Automocion, the world’s leading pressed parts manufacturer based in Spain, is working toward setting up a plant in Matsusaka, Mie Prefecture, as early as next year to produce hot-stamped parts.
The company operates factories in 100 or so locations around the globe, but this will be its first production base in Japan. The facility, estimated to cost from 5 billion yen to 10 billion yen ($43.8 million-$87.6 million), is expected to supply parts, including hot-stamped varieties, to Toyota and others.
Gestamp’s strength includes hot-stamping technology. Japanese trading house Mitsui & Co. acquired a 12% stake in the Spanish company last year.