Recently, the Korean Materials Research Institute (KIMS) Steel Materials Research Office under the Ministry of Science, Technology, Information and Communication and the Pohang Institute of Industrial Science (RIST) developed the world’s first ultra-lightweight stainless steel, which is about 20% lighter than traditional stainless steel.
The ultra-lightweight stainless steel developed this time not only changes the traditional stereotype of "stainless steel is heavy", but also does not add expensive nickel alloys, thus ensuring price competitiveness.
This research was strongly supported by the dual-use technology development project of the Military-civilian Cooperation Agency of the Korea National Defense Agency. Relevant research results were published in the international academic journal "Scientific Report" (Scientific Report), the title of the paper is "A new class of lightweight, stainless steels with ultra-high strength and large ductility" (a new type of lightweight, ultra-high strength , High ductility stainless steel). In the future, the research team will carry out follow-up research such as technology mass production.
So far, ultra-lightweight steel is made by adding light-alloying element aluminum to the steel to achieve lightweight effects. However, excessive aluminum can also cause brittleness, which can cause brittleness. Therefore, the aluminum content should not exceed 10%. In order to overcome this problem, the research team optimized the addition of carbon, manganese, chromium and other alloy elements to reduce the brittleness of steel while adding 12% aluminum. In addition, the addition of chromium promotes the formation of a dense oxide layer with a high content of aluminum and chromium on the surface of the steel, thereby ensuring that the corrosion resistance is equivalent to that of 400 series stainless steel.
Traditional stainless steel has a density of 7.9-8.0g/cm3 and is heavy. The ultra-lightweight stainless steel developed in South Korea this time added 12% aluminum, and the density was reduced to 6.3-6.5g/cm3, which was about 20% lighter. This kind of ultra-lightweight stainless steel, if it is applied first in industries such as automobiles and shipbuilding, is expected to improve fuel efficiency while reducing carbon dioxide emissions.
It can be said that this research starts from a new alloy design direction, which not only breaks through the weight limitation of traditional stainless steel, but also solves the corrosiveness and brittleness problems of ultra-lightweight steel, which is of great significance.
Stainless steel has excellent strength and ductility, as well as outstanding corrosion resistance. In addition to kitchen appliances and household appliances, it is also widely used in automotive, construction, shipbuilding, medical and other industries. It can be seen that the ultra-lightweight developed this time The application prospect of high-quality stainless steel is broad.